The pay bands were placed where they were (and have since risen to) via arbitration coming out of the white book imposed rules. There was no "mistake" made by the union. They aren't where they should be regardless.
Fucking us because we have no other option sounds great!
And someone making 212k being capped every year still has more validity in arguing for actually getting their contractual pay than someone making much less who just feels like they want to get paid more. Get over it.
There's a bill in the House that is already addressing the issue for GS employees. If it gets FAA added to it, it would solve the problem, but it won't see the light of day til Dems run the House.