Guide listing doesn’t match actual programming

Tonight, we were expecting SNL to be on at 8:30 pacific time like it usually is when there is a new episode. Our guide on tv as well as the online guide in the app indicated that it wasn't on until 11:30 and other programming would be on during the 8:30-10:00 pm slot. Normally I would record it at 8:30 and watch it around 9:00 if we were not going to be available. Tonight, we went out. We came home and SNL was in fact on and the both guides indicated Dateline should be on. It's not the end of the world by any means BUT, this is the third time actual programming has not matched what was indicated in the app and in the guide on tv via our Xfinity box.