I am guessing you have to be 120 to have this happen, I went to the old UC on this character the other day to get the music for the garrison jukebox. When I flew over it was the older zone and I did not get flagged. I have not bothered to level to 120 as I found it boring and dull in BFA, but might have to eventually if 8.2 is any good and the new place is like timeless isle.