I thinks folks are grossly underestimating the impact of AOS interviews will have on the spill over. There are 120k Green cards given every year. If USCIS does not scale quickly I think it would be impossible to complete these interviews within the same fiscal year. According to DOS anyone who is filing 485 after March 2017 will need an interview , which means everyone who is filing new.
I see EB1, EB3 and EB2 ROW are going to see a huge amount of slow down and EB2I will be a big beneficiary of it since all the existing demand in EB2I is from 2010 who dont need interviews.