diff --git a/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/OffsetStoreDao.scala b/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/OffsetStoreDao.scala
index 14f037868..e2f0c92b7 100644
--- a/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/OffsetStoreDao.scala
+++ b/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/OffsetStoreDao.scala
@@ -22,7 +22,7 @@ import akka.projection.r2dbc.internal.R2dbcOffsetStore.LatestBySlice
 @InternalApi
 private[projection] trait OffsetStoreDao {
 
-  def readTimestampOffset(): Future[immutable.IndexedSeq[R2dbcOffsetStore.RecordWithProjectionKey]]
+  def readTimestampOffset(slice: Int): Future[immutable.IndexedSeq[R2dbcOffsetStore.RecordWithProjectionKey]]
 
   def readTimestampOffset(slice: Int, pid: String): Future[Option[R2dbcOffsetStore.Record]]
 
diff --git a/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/PostgresOffsetStoreDao.scala b/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/PostgresOffsetStoreDao.scala
index 09e5cce51..074dcb8dd 100644
--- a/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/PostgresOffsetStoreDao.scala
+++ b/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/PostgresOffsetStoreDao.scala
@@ -64,8 +64,8 @@ private[projection] class PostgresOffsetStoreDao(
 
   private val selectTimestampOffsetSql: String =
     sql"""
-    SELECT projection_key, slice, persistence_id, seq_nr, timestamp_offset
-    FROM $timestampOffsetTable WHERE slice BETWEEN ? AND ? AND projection_name = ?"""
+    SELECT projection_key, persistence_id, seq_nr, timestamp_offset
+    FROM $timestampOffsetTable WHERE slice = ? AND projection_name = ? ORDER BY timestamp_offset DESC LIMIT ?"""
 
   protected def createSelectOneTimestampOffsetSql: String =
     sql"""
@@ -192,25 +192,20 @@ private[projection] class PostgresOffsetStoreDao(
           s"Expected BySlicesSourceProvider to be defined when TimestampOffset is used.")
     }
 
-  override def readTimestampOffset(): Future[immutable.IndexedSeq[R2dbcOffsetStore.RecordWithProjectionKey]] = {
-    val (minSlice, maxSlice) = {
-      sourceProvider match {
-        case Some(provider) => (provider.minSlice, provider.maxSlice)
-        case None           => (0, persistenceExt.numberOfSlices - 1)
-      }
-    }
+  override def readTimestampOffset(
+      slice: Int): Future[immutable.IndexedSeq[R2dbcOffsetStore.RecordWithProjectionKey]] = {
     r2dbcExecutor.select("read timestamp offset")(
       conn => {
         logger.trace("reading timestamp offset for [{}]", projectionId)
+        val limit = 1000 // FIXME config
         conn
           .createStatement(selectTimestampOffsetSql)
-          .bind(0, minSlice)
-          .bind(1, maxSlice)
-          .bind(2, projectionId.name)
+          .bind(0, slice)
+          .bind(1, projectionId.name)
+          .bind(2, limit)
       },
       row => {
         val projectionKey = row.get("projection_key", classOf[String])
-        val slice = row.get("slice", classOf[java.lang.Integer])
         val pid = row.get("persistence_id", classOf[String])
         val seqNr = row.get("seq_nr", classOf[java.lang.Long])
         val timestamp = row.getTimestamp("timestamp_offset")
diff --git a/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/R2dbcOffsetStore.scala b/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/R2dbcOffsetStore.scala
index c92c307fb..7e7c8abed 100644
--- a/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/R2dbcOffsetStore.scala
+++ b/akka-projection-r2dbc/src/main/scala/akka/projection/r2dbc/internal/R2dbcOffsetStore.scala
@@ -41,6 +41,9 @@ import scala.collection.immutable.TreeSet
 import scala.concurrent.ExecutionContext
 import scala.concurrent.Future
 
+import akka.stream.scaladsl.Sink
+import akka.stream.scaladsl.Source
+
 /**
  * INTERNAL API
  */
@@ -330,16 +333,29 @@ private[projection] class R2dbcOffsetStore(
   }
 
   private def readTimestampOffset(): Future[Option[TimestampOffset]] = {
+    implicit val sys = system // for implicit stream materializer
     triggerDeletionPerSlice.clear()
     val oldState = state.get()
 
-    dao.readTimestampOffset().map { recordsWithKey =>
+    val offsetSliceReadParallelism = 10 // FIXME config
+
+    val recordsWithKeyFut =
+      Source(minSlice to maxSlice)
+        .mapAsyncUnordered(offsetSliceReadParallelism) { slice =>
+          dao.readTimestampOffset(slice)
+        }
+        .mapConcat(identity)
+        .runWith(Sink.seq)
+        .map(_.toVector)(ExecutionContext.parasitic)
+
+    recordsWithKeyFut.map { recordsWithKey =>
       clearInflight()
       clearForeignOffsets()
       clearLatestSeen()
 
       val newState = {
         val s = State(recordsWithKey.map(_.record))
+        // FIXME shall we evict here, or how does that impact the logic for moreThanOneProjectionKey and foreignOffsets?
         (minSlice to maxSlice).foldLeft(s) {
           case (acc, slice) => acc.evict(slice, settings.timeWindow)
         }