bad feathers

So, it started about 10 days ago, perfectly healthy looking feathers started looking rough a bit too fast. In a couple days they looked chopped up and I was wondering what was going on when around day 5 I finally caught him preening his shoulders/wings as far as he can reach and actually biting...

I posted here about the most wonderful little budgie boy Tesla I adopted on January 1. He has been doing very well except his wing and tail feathers. :( He was reportedly from a local shelter and had a leg band which he chewed off later, and I assume he was tested for PBFD, polyoma and other bad...