I don't think you get additional TPs for AUPs on US (or other non BA airlines) sadly. It's a little known fact that most people find out the hard way.

As for the 35 v 20 debate, it sounds as though you took the flight after 28th April and you've therefore been credited at the new rates.

You can try and fight this, but it could be a lot of hassle with no guarantee of success. If you're going to qualify anyway soon, I think I'd be inclined to put this down as a lesson learned and bad luck on the timing.