Apple Watch 2 is rumoured to be an S update rather than a redesign, but wouldn't it make more sense for it to be released alongside the iPhone 7 in September? But I do think that the Bill Graham Civic building is a bit odd, Apple have only used that for big events, Apple 2 was announced there and so was the iPhone 6S, iPad Pro (12.9") and the Apple TV 4 in September of 2015.