addressed feedback

contracts/gas-snapshots/functions.gas-snapshot

@@ -1,12 +1,12 @@
-ChainSpecificUtil__getL1FeeUpperLimit_Arbitrum:test__getL1FeeUpperLimit_SuccessWhenArbitrumGoerli() (gas: 16087460)
-ChainSpecificUtil__getL1FeeUpperLimit_Arbitrum:test__getL1FeeUpperLimit_SuccessWhenArbitrumMainnet() (gas: 16087439)
-ChainSpecificUtil__getL1FeeUpperLimit_Arbitrum:test__getL1FeeUpperLimit_SuccessWhenArbitrumSepolia() (gas: 16087508)
-ChainSpecificUtil__getL1FeeUpperLimit_Base:test__getL1FeeUpperLimit_SuccessWhenBaseGoerli() (gas: 16087228)
-ChainSpecificUtil__getL1FeeUpperLimit_Base:test__getL1FeeUpperLimit_SuccessWhenBaseMainnet() (gas: 16087184)
-ChainSpecificUtil__getL1FeeUpperLimit_Base:test__getL1FeeUpperLimit_SuccessWhenBaseSepolia() (gas: 16087255)
-ChainSpecificUtil__getL1FeeUpperLimit_Optimism:test__getL1FeeUpperLimit_SuccessWhenOptimismGoerli() (gas: 16087141)
-ChainSpecificUtil__getL1FeeUpperLimit_Optimism:test__getL1FeeUpperLimit_SuccessWhenOptimismMainnet() (gas: 16087163)
-ChainSpecificUtil__getL1FeeUpperLimit_Optimism:test__getL1FeeUpperLimit_SuccessWhenOptimismSepolia() (gas: 16087206)
+ChainSpecificUtil__getL1FeeUpperLimit_Arbitrum:test__getL1FeeUpperLimit_SuccessWhenArbitrumGoerli() (gas: 16076840)
+ChainSpecificUtil__getL1FeeUpperLimit_Arbitrum:test__getL1FeeUpperLimit_SuccessWhenArbitrumMainnet() (gas: 16076819)
+ChainSpecificUtil__getL1FeeUpperLimit_Arbitrum:test__getL1FeeUpperLimit_SuccessWhenArbitrumSepolia() (gas: 16076888)
+ChainSpecificUtil__getL1FeeUpperLimit_Base:test__getL1FeeUpperLimit_SuccessWhenBaseGoerli() (gas: 16076608)
+ChainSpecificUtil__getL1FeeUpperLimit_Base:test__getL1FeeUpperLimit_SuccessWhenBaseMainnet() (gas: 16076564)
+ChainSpecificUtil__getL1FeeUpperLimit_Base:test__getL1FeeUpperLimit_SuccessWhenBaseSepolia() (gas: 16076635)
+ChainSpecificUtil__getL1FeeUpperLimit_Optimism:test__getL1FeeUpperLimit_SuccessWhenOptimismGoerli() (gas: 16076521)
+ChainSpecificUtil__getL1FeeUpperLimit_Optimism:test__getL1FeeUpperLimit_SuccessWhenOptimismMainnet() (gas: 16076543)
+ChainSpecificUtil__getL1FeeUpperLimit_Optimism:test__getL1FeeUpperLimit_SuccessWhenOptimismSepolia() (gas: 16076586)
 FunctionsBilling_Constructor:test_Constructor_Success() (gas: 17982)
 FunctionsBilling_DeleteCommitment:test_DeleteCommitment_RevertIfNotRouter() (gas: 13283)
 FunctionsBilling_DeleteCommitment:test_DeleteCommitment_Success() (gas: 15853)
@@ -208,12 +208,12 @@ FunctionsTermsOfServiceAllowList_BlockSender:test_BlockSender_Success() (gas: 97
 FunctionsTermsOfServiceAllowList_Constructor:test_Constructor_Success() (gas: 15345)
 FunctionsTermsOfServiceAllowList_GetAllAllowedSenders:test_GetAllAllowedSenders_Success() (gas: 19243)
 FunctionsTermsOfServiceAllowList_GetAllowedSendersCount:test_GetAllowedSendersCount_Success() (gas: 13332)
-FunctionsTermsOfServiceAllowList_GetAllowedSendersInRange:test_GetAllowedSendersInRange_RevertIfAllowedSendersIsEmpty() (gas: 13337196)
+FunctionsTermsOfServiceAllowList_GetAllowedSendersInRange:test_GetAllowedSendersInRange_RevertIfAllowedSendersIsEmpty() (gas: 13326576)
 FunctionsTermsOfServiceAllowList_GetAllowedSendersInRange:test_GetAllowedSendersInRange_RevertIfEndIsAfterLastAllowedSender() (gas: 16532)
 FunctionsTermsOfServiceAllowList_GetAllowedSendersInRange:test_GetAllowedSendersInRange_RevertIfStartIsAfterEnd() (gas: 13307)
 FunctionsTermsOfServiceAllowList_GetAllowedSendersInRange:test_GetAllowedSendersInRange_Success() (gas: 20335)
 FunctionsTermsOfServiceAllowList_GetBlockedSendersCount:test_GetBlockedSendersCount_Success() (gas: 13268)
-FunctionsTermsOfServiceAllowList_GetBlockedSendersInRange:test_GetBlockedSendersInRange_RevertIfAllowedSendersIsEmpty() (gas: 13337184)
+FunctionsTermsOfServiceAllowList_GetBlockedSendersInRange:test_GetBlockedSendersInRange_RevertIfAllowedSendersIsEmpty() (gas: 13326564)
 FunctionsTermsOfServiceAllowList_GetBlockedSendersInRange:test_GetBlockedSendersInRange_RevertIfEndIsAfterLastAllowedSender() (gas: 16549)
 FunctionsTermsOfServiceAllowList_GetBlockedSendersInRange:test_GetBlockedSendersInRange_RevertIfStartIsAfterEnd() (gas: 13345)
 FunctionsTermsOfServiceAllowList_GetBlockedSendersInRange:test_GetBlockedSendersInRange_Success() (gas: 18580)
@@ -224,7 +224,7 @@ FunctionsTermsOfServiceAllowList_HasAccess:test_HasAccess_TrueWhenDisabled() (ga
 FunctionsTermsOfServiceAllowList_IsBlockedSender:test_IsBlockedSender_SuccessFalse() (gas: 15776)
 FunctionsTermsOfServiceAllowList_IsBlockedSender:test_IsBlockedSender_SuccessTrue() (gas: 86974)
 FunctionsTermsOfServiceAllowList_MigratePreviouslyAllowedSenders:test_MigratePreviouslyAllowedSenders_RevertIfNotOwner() (gas: 13987)
-FunctionsTermsOfServiceAllowList_MigratePreviouslyAllowedSenders:test_MigratePreviouslyAllowedSenders_Success() (gas: 210672)
+FunctionsTermsOfServiceAllowList_MigratePreviouslyAllowedSenders:test_MigratePreviouslyAllowedSenders_Success() (gas: 210636)
 FunctionsTermsOfServiceAllowList_UnblockSender:test_UnblockSender_RevertIfNotOwner() (gas: 13548)
 FunctionsTermsOfServiceAllowList_UnblockSender:test_UnblockSender_Success() (gas: 96240)
 FunctionsTermsOfServiceAllowList_UpdateConfig:test_UpdateConfig_RevertIfNotOwner() (gas: 13819)

contracts/src/v0.8/functions/dev/v1_X/accessControl/TermsOfServiceAllowList.sol

@@ -30,6 +30,7 @@ contract TermsOfServiceAllowList is ITermsOfServiceAllowList, IAccessController,
   error InvalidUsage();
   error RecipientIsBlocked();
   error InvalidCalldata();
+  error NoPreviousToSContract();
 
   TermsOfServiceAllowListConfig private s_config;
 
@@ -202,15 +203,19 @@ contract TermsOfServiceAllowList is ITermsOfServiceAllowList, IAccessController,
     return blockedSenders;
   }
 
+  /// @inheritdoc ITermsOfServiceAllowList
   function migratePreviouslyAllowedSenders(address[] memory previousSendersToAdd) external override onlyOwner {
-    require(s_previousToSContract != address(0), "No previous ToS contract");
+    if (s_previousToSContract == address(0)) {
+      revert NoPreviousToSContract();
+    }
     IAccessController previousToSContract = IAccessController(s_previousToSContract);
     for (uint256 i = 0; i < previousSendersToAdd.length; ++i) {
       if (
-        previousToSContract.hasAccess(previousSendersToAdd[i], "") &&
-        !s_blockedSenders.contains(previousSendersToAdd[i])
+        previousToSContract.hasAccess(previousSendersToAdd[i], "")
       ) {
-        s_allowedSenders.add(previousSendersToAdd[i]);
+        if (!s_blockedSenders.contains(previousSendersToAdd[i])) {
+          s_allowedSenders.add(previousSendersToAdd[i]);
+        }
       }
     }
   }