First Dubbel

I cooked up a recipe for a dubbel this weekend and am planning on brewing this week and pitching onto my cake from a belgian IPA but am confused when to add the candy sugar. I plan on making my own but don't know whether to add it during the boil or straight into the fermenter. I've heard that it can be added to the fermenter to help push ahead the yeast when the gravity stalls out around 1.020. Does it matter when I add it?

I just add it to the boil, as a late addition, with say 15-min. left. I Let the temp ramp up and rouse the yeast after a couple of weeks. I have one going now that I brewed on August second that is just about ready to bottle. The gravity was down to 1.014 when I racked to secondary on September 19th. (gravity sample tasted awesome...) the waiting is the hard part...

I prefer to add directly to the primary. I just boil the sugar briefly in enough water to dilute it, then pour it in.This can be easier on the yeast because it is less work at the start of fermentation. With you pitching onto a yeast cake I don't think this will be an issue for you.

I add my candi syrup on the 3rd day of fermentation, I feel that this stresses the yeast less.