[Cata Classic] Realm transferred, map is now unexplored

Hi, I hope I’m posting in the correct area for this. I transferred this character from Gehennas to Golemagg today and Outland/Northrend are now completely unexplored. (I have the Northrend explorer achievement as well) Only these 2 areas seem affected, Kalimdor/Eastern Kingdoms are still ok. Is this a known issue/can anything be done? Thanks in advance.