Turning the beat around was a conscious decision. Messing with the downbeat was always a bit of a habit of mine and Mick would design bass parts to compliment this approach (‘Still Life In Mobile Homes’, ‘The Art Of Parties’ for example). In the case of ‘My New Career’ the beat turn around was employed to accentuated the chorus vocal line.
Drums sounds were generally heavily compressed in those days, it was a contemporary sound of that time. I wasn’t involved in sound engineering back then so it would have been the producers job.