I can answer your first one but I’ll leave your second one to someone smarter than me.
My drives are already going noticeably further after a couple of weeks BUT I am blowing them all over the place. My predominant miss currently is a huge block right. My irons and hybrids haven’t been too bad but I can’t definitively say if they aren’t worse/better.
I would be extremely worried about this if I hadn’t read of other people having similar experiences, so I’m expecting this to moderate over the next month or so.