Crash when changing Level Sequence to Level Sequence Actor

I upgraded my project from 5.3 to 5.4 and now to 5.4.1.

If I stop a Level Sequence Actor, change the Sequence and Play the game crashes with

Error: appError called: Assertion failed: StartIndex >= 0 && StartIndex <= Array.Num() [File:D:\build++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\BitArray.h] [Line: 1816]

that does not happen in PIE.

I tryied with new Level Sequences and with no tracks at all still same result.

Rest of Stack Trace:

TurtlesQuest!FMovieSceneSpawnRegister::ForgetExternallyOwnedSpawnedObjects()
TurtlesQuest!UE::MovieScene::FSequenceInstance::Finish()
TurtlesQuest!FMovieSceneEntitySystemRunner::QueueFinalUpdateImpl()
TurtlesQuest!FMovieSceneEntitySystemRunner::QueueFinalUpdate()
TurtlesQuest!UMovieSceneSequencePlayer::StopInternal()
TurtlesQuest!UMovieSceneSequencePlayer::Initialize()
TurtlesQuest!ULevelSequencePlayer::Initialize()
TurtlesQuest!ALevelSequenceActor::execSetSequence()
TurtlesQuest!UFunction::Invoke()
TurtlesQuest!UObject::CallFunction()
TurtlesQuest!UObject::ProcessContextOpcode()
TurtlesQuest!ProcessLocalScriptFunction()
TurtlesQuest!ProcessScriptFunction<void (__cdecl*)(UObject * __ptr64,FFrame & __ptr64,void * __ptr64)>()
TurtlesQuest!ProcessLocalFunction()
TurtlesQuest!ProcessLocalScriptFunction()
TurtlesQuest!UObject::ProcessInternal()
TurtlesQuest!UFunction::Invoke()
TurtlesQuest!UObject::ProcessEvent()
TurtlesQuest!AActor::ProcessEvent()
TurtlesQuest!TScriptDelegate::ProcessDelegate()
TurtlesQuest!FInputActionHandlerDynamicSignature_DelegateWrapper()
TurtlesQuest!FInputActionUnifiedDelegate::Execute()
TurtlesQuest!UPlayerInput::EvaluateInputDelegates()
TurtlesQuest!UEnhancedPlayerInput::EvaluateInputDelegates()
TurtlesQuest!UPlayerInput::ProcessInputStack()
TurtlesQuest!APlayerController::ProcessPlayerInput()
TurtlesQuest!APlayerController::TickPlayerInput()
TurtlesQuest!APlayerController::PlayerTick()
TurtlesQuest!APlayerController::TickActor()
TurtlesQuest!FActorTickFunction::ExecuteTick()
TurtlesQuest!FTickFunctionTask::DoTask()
TurtlesQuest!TGraphTask::ExecuteTask()
TurtlesQuest!FNamedTaskThread::ProcessTasksNamedThread()
TurtlesQuest!FNamedTaskThread::ProcessTasksUntilQuit()
TurtlesQuest!FTaskGraphCompatibilityImplementation::WaitUntilTasksComplete()
TurtlesQuest!FTickTaskSequencer::ReleaseTickGroup()
TurtlesQuest!FTickTaskManager::RunTickGroup()
TurtlesQuest!UWorld::RunTickGroup()
TurtlesQuest!UWorld::Tick()
TurtlesQuest!UGameEngine::Tick()
TurtlesQuest!FEngineLoop::Tick()
TurtlesQuest!GuardedMain()
TurtlesQuest!GuardedMainWrapper()
TurtlesQuest!LaunchWindowsStartup()
TurtlesQuest!WinMain()
TurtlesQuest!__scrt_common_main_seh() [D:\a_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll
UPDATE:
I also tryied it on a brand new project and it’s definetly a bug.

I opened a Bug report with Case # 02323868