Currently, properties marked DuplicateTransient will be reset to default when their actor is moved to a different level. This happens because we use the clipboard to virtually cut the actor out of one level and paste it into another, so it's still a duplication under the hood. However, it's more intuitive to think a "move" transaction would relocate the existing instance and not duplicate it and delete the original. Therefore, we'd expect the DuplicateTransient property to still be set after a move.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-52678 in the post.