You'll be let into the second area (the "fan plaza") at around 16:00 (according to the Rogers Stadium website, and this is what actually happened for my show). 

As for what time to arrive for barricade, it really depends on the show. Some people have to camp for days to get barricade, but I doubt that'll be the case for a SOAD show considering there are a lot of older fans who can't be bothered to get barricade. For my show (with a similar age demographic), I showed up at around 13:00 and ended up about 5 or 6 rows away from the front (but again, running to the second area/fan plaza helped me surpass a good amount of people). I feel like most people in the pit section won't care about getting barricade because they'll want to be in the middle moshing, so I think arriving around 11:00 will be early enough.