It varies
There is no real way to get a fix on the time it takes to get AP & EAD approval. In my case it took approximately three and a half months from RD to get AP approval. I have still not got my EAD. So, you can assume it will take a couple of months. Hope this helps
EB2(RIR), RD:04/30, ND: 06/29, AP: 08/17, FP SCHD:11/03