I agree with Pwnstix. It especially bugs me that, if you have triggered both quests, the game locks you into Iron Bull's non-time sensitive quest immediately upon entering the region and will not let you leave the quest area until it is complete and you've been transported back to Skyhold, thus forcing a failure in the Sutherland quest.
This seems to be a major oversight and I can't fix it without going back nearly 80 hours of gameplay to a save where only one quest was triggered. :-[ Very disappointing.