Don’t they have large numbers still in crates unassembled? And the M1A1 is still a first rate tank, especially if you have a lot of them, and especially if they are already in theater.
I think they finally ran through their kit backlog - supposedly the latest deal that Obama pushed through after Mubarak was removed was half kits, half completed tanks (50 or 60 of each) - the kits did not have the DU armor enhancements and some other goodies found on US-issue M1A1s, but I think the complete tanks they have either just gotten or are to get soon are US-issue tanks with the full suite of goodies.