I didn't know quite how to word the title so I'll explain. When you start a new character and you accept a guild daily it will be in your first faction region (Auridon/Glenumbra/Stonefalls), but for most if not all of my characters I cannot unlock the next region until after some random trigger, or reaching level 50. I gave up doing the dailies on most characters because there was no point in revisiting the same public dungeon for the Mages Guild, or destroying the same dolmens.
I have a new character now, just turned level 16. They haven't done any of the Main/Fighters/Mages questlines, but the first quest of each is active. I go back everyday for a daily and it will always be Auridon. At the moment I am doing the repeatable quests for the Thieves Guild and Dark Brotherhood. All of their quests were in Auridon until I reached level 15, then the DB quests started being in Grahtwood, and when I reached 16 the TG quests moved to Grahtwood. Strange that they weren't the same level, but I have no other info on this.
So does anyone know about the Fighters/Mages guilds? Do they advance when you advance through their questlines? I would test it but I finished their dailies today so I can only report tomorrow. Also I wasn't sure which terms to search the forums for to find a similar topic, so if this has been answered and explained I would appreciate a link.
PS5 EU.