diff --git a/frontend/__snapshots__/posthog-3000-sidebar--dashboards.png b/frontend/__snapshots__/posthog-3000-sidebar--dashboards.png
index 692ac2b0b1876..e37465625ced2 100644
Binary files a/frontend/__snapshots__/posthog-3000-sidebar--dashboards.png and b/frontend/__snapshots__/posthog-3000-sidebar--dashboards.png differ
diff --git a/frontend/src/layout/navigation-3000/sidebars/personsAndGroups.ts b/frontend/src/layout/navigation-3000/sidebars/personsAndGroups.ts
index 7dcd526374a3c..2cefac31cf5ba 100644
--- a/frontend/src/layout/navigation-3000/sidebars/personsAndGroups.ts
+++ b/frontend/src/layout/navigation-3000/sidebars/personsAndGroups.ts
@@ -90,7 +90,7 @@ export const personsAndGroupsSidebarLogic = kea<personsAndGroupsSidebarLogicType
                             minimumBatchSize: 100,
                         },
                     } as SidebarCategory,
-                    ...groupTypes.map(
+                    ...Array.from(groupTypes.values()).map(
                         (groupType) =>
                             ({
                                 key: `groups-${groupType.group_type_index}`,
@@ -120,7 +120,7 @@ export const personsAndGroupsSidebarLogic = kea<personsAndGroupsSidebarLogicType
                 Array(5)
                     .fill(null)
                     .map((_, groupTypeIndex) => (state) => {
-                        if (s.groupTypes(state).length > groupTypeIndex) {
+                        if (s.groupTypes(state)[groupTypeIndex]) {
                             groupsListLogic({ groupTypeIndex }).mount()
                             return groupsListLogic({ groupTypeIndex }).selectors.groups(state)
                         }
@@ -140,7 +140,7 @@ export const personsAndGroupsSidebarLogic = kea<personsAndGroupsSidebarLogicType
                 Array(5)
                     .fill(null)
                     .map((_, groupTypeIndex) => (state) => {
-                        if (s.groupTypes(state).length > groupTypeIndex) {
+                        if (s.groupTypes(state)[groupTypeIndex]) {
                             groupsListLogic({ groupTypeIndex }).mount()
                             return groupsListLogic({ groupTypeIndex }).selectors.groupsLoading(state)
                         }
@@ -184,7 +184,7 @@ export const personsAndGroupsSidebarLogic = kea<personsAndGroupsSidebarLogicType
         searchTerm: (searchTerm) => {
             actions.setPersonsListFilters({ search: searchTerm })
             actions.loadPersons()
-            for (const { group_type_index: groupTypeIndex } of values.groupTypes) {
+            for (const { group_type_index: groupTypeIndex } of Object.values(values.groupTypes)) {
                 groupsListLogic({ groupTypeIndex }).actions.setSearch(searchTerm, false)
             }
         },
diff --git a/frontend/src/lib/components/TaxonomicFilter/taxonomicFilterLogic.tsx b/frontend/src/lib/components/TaxonomicFilter/taxonomicFilterLogic.tsx
index f15d9b8778d3c..f1c1a7630f65f 100644
--- a/frontend/src/lib/components/TaxonomicFilter/taxonomicFilterLogic.tsx
+++ b/frontend/src/lib/components/TaxonomicFilter/taxonomicFilterLogic.tsx
@@ -453,7 +453,7 @@ export const taxonomicFilterLogic = kea<taxonomicFilterLogicType>({
         groupAnalyticsTaxonomicGroupNames: [
             (s) => [s.groupTypes, s.currentTeamId, s.aggregationLabel],
             (groupTypes, teamId, aggregationLabel): TaxonomicFilterGroup[] =>
-                groupTypes.map((type) => ({
+                Array.from(groupTypes.values()).map((type) => ({
                     name: `${capitalizeFirstLetter(aggregationLabel(type.group_type_index).plural)}`,
                     searchPlaceholder: `${aggregationLabel(type.group_type_index).plural}`,
                     type: `${TaxonomicFilterGroupType.GroupNamesPrefix}_${type.group_type_index}` as unknown as TaxonomicFilterGroupType,
@@ -470,7 +470,7 @@ export const taxonomicFilterLogic = kea<taxonomicFilterLogicType>({
         groupAnalyticsTaxonomicGroups: [
             (s) => [s.groupTypes, s.currentTeamId, s.aggregationLabel],
             (groupTypes, teamId, aggregationLabel): TaxonomicFilterGroup[] =>
-                groupTypes.map((type) => ({
+                Array.from(groupTypes.values()).map((type) => ({
                     name: `${capitalizeFirstLetter(aggregationLabel(type.group_type_index).singular)} properties`,
                     searchPlaceholder: `${aggregationLabel(type.group_type_index).singular} properties`,
                     type: `${TaxonomicFilterGroupType.GroupsPrefix}_${type.group_type_index}` as unknown as TaxonomicFilterGroupType,
diff --git a/frontend/src/models/groupsModel.ts b/frontend/src/models/groupsModel.ts
index 458f71e70e7c5..9f7cd247a88de 100644
--- a/frontend/src/models/groupsModel.ts
+++ b/frontend/src/models/groupsModel.ts
@@ -1,6 +1,6 @@
 import { kea, path, connect, selectors, events } from 'kea'
 import api from 'lib/api'
-import { GroupType } from '~/types'
+import { GroupType, GroupTypeIndex } from '~/types'
 import { teamLogic } from 'scenes/teamLogic'
 import type { groupsModelType } from './groupsModelType'
 import { TaxonomicFilterGroupType } from 'lib/components/TaxonomicFilter/types'
@@ -40,26 +40,22 @@ export const groupsModel = kea<groupsModelType>([
     selectors({
         groupTypes: [
             (s) => [s.groupTypesRaw],
-            (groupTypesRaw) => {
-                const groupTypes: GroupType[] = new Array(groupTypesRaw.length)
-
-                for (const groupType of groupTypesRaw) {
-                    groupTypes[groupType.group_type_index] = groupType
-                }
-
-                return groupTypes
-            },
+            (groupTypesRaw) =>
+                new Map<GroupTypeIndex, GroupType>(
+                    groupTypesRaw.map((groupType) => [groupType.group_type_index, groupType])
+                ),
         ],
         groupTypesLoading: [(s) => [s.groupTypesRawLoading], (groupTypesRawLoading) => groupTypesRawLoading],
 
         showGroupsOptions: [
             (s) => [s.groupsAccessStatus, s.groupsEnabled, s.groupTypes],
-            (status, enabled, groupTypes) => status !== GroupsAccessStatus.Hidden || (enabled && groupTypes.length > 0),
+            (status, enabled, groupTypes) =>
+                status !== GroupsAccessStatus.Hidden || (enabled && Array.from(groupTypes.values()).length > 0),
         ],
         groupsTaxonomicTypes: [
             (s) => [s.groupTypes],
             (groupTypes): TaxonomicFilterGroupType[] => {
-                return groupTypes.map(
+                return Array.from(groupTypes.values()).map(
                     (groupType: GroupType) =>
                         `${TaxonomicFilterGroupType.GroupsPrefix}_${groupType.group_type_index}` as unknown as TaxonomicFilterGroupType
                 )
@@ -68,7 +64,7 @@ export const groupsModel = kea<groupsModelType>([
         groupNamesTaxonomicTypes: [
             (s) => [s.groupTypes],
             (groupTypes): TaxonomicFilterGroupType[] => {
-                return groupTypes.map(
+                return Array.from(groupTypes.values()).map(
                     (groupType: GroupType) =>
                         `${TaxonomicFilterGroupType.GroupNamesPrefix}_${groupType.group_type_index}` as unknown as TaxonomicFilterGroupType
                 )
@@ -78,12 +74,18 @@ export const groupsModel = kea<groupsModelType>([
             (s) => [s.groupTypes],
             (groupTypes) =>
                 (groupTypeIndex: number | null | undefined, deferToUserWording: boolean = false): Noun => {
-                    if (groupTypeIndex != undefined && groupTypes.length > 0 && groupTypes[groupTypeIndex]) {
-                        const groupType = groupTypes[groupTypeIndex]
-
-                        return {
-                            singular: groupType.name_plural || groupType.group_type,
-                            plural: groupType.name_plural || `${groupType.group_type}(s)`,
+                    if (groupTypeIndex != undefined) {
+                        const groupType = groupTypes.get(groupTypeIndex as GroupTypeIndex)
+                        if (groupType) {
+                            return {
+                                singular: groupType.name_plural || groupType.group_type,
+                                plural: groupType.name_plural || `${groupType.group_type}(s)`,
+                            }
+                        } else {
+                            return {
+                                singular: 'unknown group',
+                                plural: 'unknown groups',
+                            }
                         }
                     }
                     return deferToUserWording
diff --git a/frontend/src/scenes/cohorts/CohortFilters/cohortFieldLogic.ts b/frontend/src/scenes/cohorts/CohortFilters/cohortFieldLogic.ts
index f425e299aca12..7ab38207877e3 100644
--- a/frontend/src/scenes/cohorts/CohortFilters/cohortFieldLogic.ts
+++ b/frontend/src/scenes/cohorts/CohortFilters/cohortFieldLogic.ts
@@ -71,10 +71,12 @@ export const cohortFieldLogic = kea<cohortFieldLogicType>([
                                 label: 'Persons',
                             },
                             ...Object.fromEntries(
-                                groupTypes.map((type) => [
-                                    `${ActorGroupType.GroupPrefix}_${type.group_type_index}`,
-                                    { label: aggregationLabel(type.group_type_index).plural },
-                                ])
+                                Array.from(groupTypes.values())
+                                    .map((type) => [
+                                        `${ActorGroupType.GroupPrefix}_${type.group_type_index}`,
+                                        { label: aggregationLabel(type.group_type_index).plural },
+                                    ])
+                                    .filter(Boolean)
                             ),
                         },
                     },
diff --git a/frontend/src/scenes/data-management/properties/propertyDefinitionsTableLogic.ts b/frontend/src/scenes/data-management/properties/propertyDefinitionsTableLogic.ts
index 7e475bc95a1f9..933c08d6442fc 100644
--- a/frontend/src/scenes/data-management/properties/propertyDefinitionsTableLogic.ts
+++ b/frontend/src/scenes/data-management/properties/propertyDefinitionsTableLogic.ts
@@ -100,7 +100,7 @@ export const propertyDefinitionsTableLogic = kea<propertyDefinitionsTableLogicTy
         propertyTypeOptions: [
             (s) => [s.groupTypes, s.aggregationLabel],
             (groupTypes, aggregationLabel) => {
-                const groupChoices: Array<LemonSelectOption<string>> = groupTypes.map((type) => ({
+                const groupChoices: Array<LemonSelectOption<string>> = Array.from(groupTypes.values()).map((type) => ({
                     label: `${capitalizeFirstLetter(aggregationLabel(type.group_type_index).singular)} properties`,
                     value: `group::${type.group_type_index}`,
                 }))
diff --git a/frontend/src/scenes/experiments/Experiment.tsx b/frontend/src/scenes/experiments/Experiment.tsx
index 2717a1f523750..97a6a198f5363 100644
--- a/frontend/src/scenes/experiments/Experiment.tsx
+++ b/frontend/src/scenes/experiments/Experiment.tsx
@@ -63,6 +63,7 @@ export function Experiment(): JSX.Element {
         flagImplementationWarning,
         props,
         aggregationLabel,
+        showGroupsOptions,
         groupTypes,
         experimentMissing,
     } = useValues(experimentLogic)
@@ -338,7 +339,7 @@ export function Experiment(): JSX.Element {
                                                 </Link>
                                             )}
                                         </div>
-                                        {experimentId === 'new' && groupTypes.length > 0 && (
+                                        {experimentId === 'new' && showGroupsOptions && (
                                             <>
                                                 <div className="mt-4">
                                                     <strong>Default participant type</strong>
@@ -371,7 +372,7 @@ export function Experiment(): JSX.Element {
                                                     }}
                                                     options={[
                                                         { value: -1, label: 'Persons' },
-                                                        ...groupTypes.map((groupType) => ({
+                                                        ...Array.from(groupTypes.values()).map((groupType) => ({
                                                             value: groupType.group_type_index,
                                                             label: capitalizeFirstLetter(
                                                                 aggregationLabel(groupType.group_type_index).plural
diff --git a/frontend/src/scenes/experiments/experimentLogic.tsx b/frontend/src/scenes/experiments/experimentLogic.tsx
index b75e1c68251a0..fdc993be666cd 100644
--- a/frontend/src/scenes/experiments/experimentLogic.tsx
+++ b/frontend/src/scenes/experiments/experimentLogic.tsx
@@ -80,7 +80,7 @@ export const experimentLogic = kea<experimentLogicType>([
     key((props) => props.experimentId || 'new'),
     path((key) => ['scenes', 'experiment', 'experimentLogic', key]),
     connect(() => ({
-        values: [teamLogic, ['currentTeamId'], groupsModel, ['aggregationLabel', 'groupTypes']],
+        values: [teamLogic, ['currentTeamId'], groupsModel, ['aggregationLabel', 'groupTypes', 'showGroupsOptions']],
         actions: [
             experimentsLogic,
             ['updateExperiments', 'addToExperiments'],
diff --git a/frontend/src/scenes/feature-flags/FeatureFlagInstructions.tsx b/frontend/src/scenes/feature-flags/FeatureFlagInstructions.tsx
index 2c32d7f615bf3..eadbc456bf678 100644
--- a/frontend/src/scenes/feature-flags/FeatureFlagInstructions.tsx
+++ b/frontend/src/scenes/feature-flags/FeatureFlagInstructions.tsx
@@ -3,7 +3,7 @@ import { useActions, useValues } from 'kea'
 import { IconInfo, IconOpenInNew } from 'lib/lemon-ui/icons'
 import './FeatureFlagInstructions.scss'
 import { LemonCheckbox, LemonSelect } from '@posthog/lemon-ui'
-import { FeatureFlagType } from '~/types'
+import { FeatureFlagType, GroupTypeIndex } from '~/types'
 import {
     BOOTSTRAPPING_OPTIONS,
     FF_ANCHOR,
@@ -66,7 +66,7 @@ export function CodeInstructions({
     const { groupTypes } = useValues(groupsModel)
     const groupType =
         featureFlag?.filters?.aggregation_group_type_index != null
-            ? groupTypes[featureFlag?.filters?.aggregation_group_type_index]
+            ? groupTypes.get(featureFlag.filters.aggregation_group_type_index as GroupTypeIndex)
             : undefined
 
     const { reportFlagsCodeExampleInteraction, reportFlagsCodeExampleLanguage } = useActions(eventUsageLogic)
diff --git a/frontend/src/scenes/feature-flags/FeatureFlagReleaseConditions.tsx b/frontend/src/scenes/feature-flags/FeatureFlagReleaseConditions.tsx
index 88b7ccf9e728e..d16ffe3c2d065 100644
--- a/frontend/src/scenes/feature-flags/FeatureFlagReleaseConditions.tsx
+++ b/frontend/src/scenes/feature-flags/FeatureFlagReleaseConditions.tsx
@@ -440,7 +440,7 @@ export function FeatureFlagReleaseConditions({
                             <Select.Option key={-1} value={-1}>
                                 Users
                             </Select.Option>
-                            {groupTypes.map((groupType) => (
+                            {Array.from(groupTypes.values()).map((groupType) => (
                                 <Select.Option key={groupType.group_type_index} value={groupType.group_type_index}>
                                     {capitalizeFirstLetter(aggregationLabel(groupType.group_type_index).plural)}
                                 </Select.Option>
diff --git a/frontend/src/scenes/feature-flags/featureFlagLogic.ts b/frontend/src/scenes/feature-flags/featureFlagLogic.ts
index 172ca75db8329..e145ddc23056f 100644
--- a/frontend/src/scenes/feature-flags/featureFlagLogic.ts
+++ b/frontend/src/scenes/feature-flags/featureFlagLogic.ts
@@ -749,9 +749,9 @@ export const featureFlagLogic = kea<featureFlagLogicType>([
                 variantRolloutSum === 100,
         ],
         aggregationTargetName: [
-            (s) => [s.featureFlag, s.groupTypes, s.aggregationLabel],
-            (featureFlag, groupTypes, aggregationLabel): string => {
-                if (featureFlag && featureFlag.filters.aggregation_group_type_index != null && groupTypes.length > 0) {
+            (s) => [s.featureFlag, s.aggregationLabel],
+            (featureFlag, aggregationLabel): string => {
+                if (featureFlag && featureFlag.filters.aggregation_group_type_index != null) {
                     return aggregationLabel(featureFlag.filters.aggregation_group_type_index).plural
                 }
                 return 'users'
diff --git a/frontend/src/scenes/groups/Group.tsx b/frontend/src/scenes/groups/Group.tsx
index f3ed2116c2aed..21c53e74133f4 100644
--- a/frontend/src/scenes/groups/Group.tsx
+++ b/frontend/src/scenes/groups/Group.tsx
@@ -69,7 +69,7 @@ export function Group(): JSX.Element {
     const { groupKey, groupTypeIndex } = logicProps
     const { setGroupEventsQuery } = useActions(groupLogic)
 
-    if (!groupData) {
+    if (!groupData || !groupType) {
         return groupDataLoading ? <SpinnerOverlay sceneLevel /> : <NotFound object="group" />
     }
 
diff --git a/frontend/src/scenes/groups/GroupsTabs.tsx b/frontend/src/scenes/groups/GroupsTabs.tsx
index 82b3d7d297cf0..89900d8054480 100644
--- a/frontend/src/scenes/groups/GroupsTabs.tsx
+++ b/frontend/src/scenes/groups/GroupsTabs.tsx
@@ -32,7 +32,7 @@ export function GroupsTabs({ activeGroupTypeIndex }: { activeGroupTypeIndex: num
                               link: urls.groups(0),
                           },
                       ]
-                    : groupTypes.map(
+                    : Array.from(groupTypes.values()).map(
                           (groupType) =>
                               ({
                                   label: capitalizeFirstLetter(aggregationLabel(groupType.group_type_index).plural),
diff --git a/frontend/src/scenes/groups/groupLogic.ts b/frontend/src/scenes/groups/groupLogic.ts
index 0800a07890f14..dce2cfdc6e04b 100644
--- a/frontend/src/scenes/groups/groupLogic.ts
+++ b/frontend/src/scenes/groups/groupLogic.ts
@@ -3,7 +3,7 @@ import api from 'lib/api'
 import { toParams } from 'lib/utils'
 import { teamLogic } from 'scenes/teamLogic'
 import { groupsModel } from '~/models/groupsModel'
-import { Breadcrumb, Group, PropertyFilterType, PropertyOperator } from '~/types'
+import { Breadcrumb, Group, GroupTypeIndex, PropertyFilterType, PropertyOperator } from '~/types'
 import type { groupLogicType } from './groupLogicType'
 import { urls } from 'scenes/urls'
 import { capitalizeFirstLetter } from 'lib/utils'
@@ -98,7 +98,7 @@ export const groupLogic = kea<groupLogicType>([
         ],
         groupType: [
             (s, p) => [s.groupTypes, p.groupTypeIndex],
-            (groupTypes, index): string => groupTypes[index]?.group_type,
+            (groupTypes, index): string | null => groupTypes.get(index as GroupTypeIndex)?.group_type ?? null,
         ],
         breadcrumbs: [
             (s, p) => [s.groupTypeName, p.groupTypeIndex, p.groupKey, s.groupData],
diff --git a/frontend/src/scenes/insights/filters/AggregationSelect.tsx b/frontend/src/scenes/insights/filters/AggregationSelect.tsx
index a4ef9cc6cfb52..766860da847a8 100644
--- a/frontend/src/scenes/insights/filters/AggregationSelect.tsx
+++ b/frontend/src/scenes/insights/filters/AggregationSelect.tsx
@@ -84,7 +84,7 @@ export function AggregationSelect({
     if (needsUpgradeForGroups || canStartUsingGroups) {
         optionSections[0].footer = <GroupIntroductionFooter needsUpgrade={needsUpgradeForGroups} />
     } else {
-        groupTypes.forEach((groupType) => {
+        Array.from(groupTypes.values()).forEach((groupType) => {
             baseValues.push(`$group_${groupType.group_type_index}`)
             optionSections[0].options.push({
                 value: `$group_${groupType.group_type_index}`,
diff --git a/frontend/src/scenes/project/Settings/GroupAnalytics.tsx b/frontend/src/scenes/project/Settings/GroupAnalytics.tsx
index ae5c1ef2c8f98..4d563af695bdb 100644
--- a/frontend/src/scenes/project/Settings/GroupAnalytics.tsx
+++ b/frontend/src/scenes/project/Settings/GroupAnalytics.tsx
@@ -81,7 +81,7 @@ export function GroupAnalytics(): JSX.Element | null {
                 </LemonBanner>
             )}
 
-            <LemonTable columns={columns} dataSource={groupTypes} loading={groupTypesLoading} />
+            <LemonTable columns={columns} dataSource={Array.from(groupTypes.values())} loading={groupTypesLoading} />
 
             <div className="flex gap-2 mt-4">
                 <LemonButton type="primary" disabled={!hasChanges} onClick={save}>
diff --git a/frontend/src/scenes/project/Settings/groupAnalyticsConfigLogic.ts b/frontend/src/scenes/project/Settings/groupAnalyticsConfigLogic.ts
index 22c9aed1ffafc..f5ac88fb37b6d 100644
--- a/frontend/src/scenes/project/Settings/groupAnalyticsConfigLogic.ts
+++ b/frontend/src/scenes/project/Settings/groupAnalyticsConfigLogic.ts
@@ -42,7 +42,7 @@ export const groupAnalyticsConfigLogic = kea<groupAnalyticsConfigLogicType>({
     listeners: ({ values, actions }) => ({
         save: async () => {
             const { groupTypes, singularChanges, pluralChanges } = values
-            const payload = groupTypes.map((groupType) => {
+            const payload = Array.from(groupTypes.values()).map((groupType) => {
                 const result = { ...groupType }
                 if (singularChanges[groupType.group_type_index]) {
                     result.name_singular = singularChanges[groupType.group_type_index]
diff --git a/frontend/src/scenes/trends/mathsLogic.tsx b/frontend/src/scenes/trends/mathsLogic.tsx
index e62d0a64b308f..bbf2374a00977 100644
--- a/frontend/src/scenes/trends/mathsLogic.tsx
+++ b/frontend/src/scenes/trends/mathsLogic.tsx
@@ -324,27 +324,29 @@ export const mathsLogic = kea<mathsLogicType>({
             (s) => [s.groupTypes, s.aggregationLabel],
             (groupTypes, aggregationLabel) =>
                 Object.fromEntries(
-                    groupTypes.map((groupType) => [
-                        apiValueToMathType('unique_group', groupType.group_type_index),
-                        {
-                            name: `Unique ${aggregationLabel(groupType.group_type_index).plural}`,
-                            shortName: `unique ${aggregationLabel(groupType.group_type_index).plural}`,
-                            description: (
-                                <>
-                                    Number of unique {aggregationLabel(groupType.group_type_index).plural} who performed
-                                    the event in the specified period.
-                                    <br />
-                                    <br />
-                                    <i>
-                                        Example: If 7 users in a single $
-                                        {aggregationLabel(groupType.group_type_index).singular} perform an event 9 times
-                                        in the given period, it counts only as 1.
-                                    </i>
-                                </>
-                            ),
-                            category: MathCategory.ActorCount,
-                        } as MathDefinition,
-                    ])
+                    Array.from(groupTypes.values())
+                        .map((groupType) => [
+                            apiValueToMathType('unique_group', groupType.group_type_index),
+                            {
+                                name: `Unique ${aggregationLabel(groupType.group_type_index).plural}`,
+                                shortName: `unique ${aggregationLabel(groupType.group_type_index).plural}`,
+                                description: (
+                                    <>
+                                        Number of unique {aggregationLabel(groupType.group_type_index).plural} who
+                                        performed the event in the specified period.
+                                        <br />
+                                        <br />
+                                        <i>
+                                            Example: If 7 users in a single $
+                                            {aggregationLabel(groupType.group_type_index).singular} perform an event 9
+                                            times in the given period, it counts only as 1.
+                                        </i>
+                                    </>
+                                ),
+                                category: MathCategory.ActorCount,
+                            } as MathDefinition,
+                        ])
+                        .filter(Boolean)
                 ),
         ],
     },
diff --git a/frontend/src/types.ts b/frontend/src/types.ts
index c59ab2d0a9f50..c29dc07b9f987 100644
--- a/frontend/src/types.ts
+++ b/frontend/src/types.ts
@@ -2473,9 +2473,11 @@ export interface PersonProperty {
     count: number
 }
 
+export type GroupTypeIndex = 0 | 1 | 2 | 3 | 4
+
 export interface GroupType {
     group_type: string
-    group_type_index: number
+    group_type_index: GroupTypeIndex
     name_singular?: string | null
     name_plural?: string | null
 }
@@ -2483,7 +2485,7 @@ export interface GroupType {
 export type GroupTypeProperties = Record<number, Array<PersonProperty>>
 
 export interface Group {
-    group_type_index: number
+    group_type_index: GroupTypeIndex
     group_key: string
     created_at: string
     group_properties: Record<string, any>