<<The USPTO has a huge backlog and moves with the speed of a hippopotamus.>>
According to Wiki, "despite its stocky shape and short legs, it can easily outrun a human. Hippos have been clocked at 30 km/h (19 mph) over short distances."
Seriously, the USPTO is supposed to move reissuances to the top of the pile, but I have to think that if they did act favorably, the next step would be litigation (TEVA seeking an injunction, Mylan and MNTA seeking to invalidate the action and it is hard to beleive that would be resolved quickly.