UAIPerceptionSystem::Tick() is not called after level reloading.
When Debugging, UAIPerceptionSystem::CurrentTime is always 0, and UAIPerceptionSystem::SourcesToRegister always contains sources to register without registering them.
It is worth noting that in these cases the first element of the SourcesToRegister array has source STALE; when the Perception System is correctly working instead, at the first call of UAIPerceptionSystem::PerformSourceRegistration() the first element of the array is the SpectatorPawn (tests were made using the default class, not an inherited one).
Results: The level is reloaded but the perception system is not working.
Expected: The perception systems should continue to work as usual.
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-85899 in the post.