Hi! I spent several days playing Sorcerer’s when I was at WDW this past August. To answer your question, each portal takes between 3-5 minutes. The delay comes if there are people queued up ahead of you to use the same portal. I’d have to check my map, but I want to say there are 5 portals in each of the lands and most of the tasks require you to visit each portal, but it seems like the next portal you’re sent to is randomly chosen.