Two Questions!

A) I notice my bench is beginning to plateau... the good news is that my reps are heavier than they have ever been WOOOO WOOO. So since my squat and dead keep going up do I continue with this workout or switch it up, because for the last six weeks of my cut I was thinking about jumping over to HST (2 weeks at 15reps, 2 weeks at 10reps, and 2 weeks at 5reps)

B) A couple years back I jumped from parallel squats to Ass2Grass squats. After talking to the athletic trainer at my school I am considering going back to parallel squats as they said pretty much no movement in sports except maybe wresting is going to go below parallel in that stance and that anything more than parallel is just un-needed stress on the knees and a good way to dislocate something and that going below parallel has little benefit. They also said A2G squatting is really only necessary in powerlifting. Anyways now I know EVERYONE or at least most on this board are advocates of A2G squatting so I would like some input please

I know going A2G my squats are at least 100lbs lighter and a lot of times my knees want to give out on the up motion