MEPCOM runs their own show AFAIK. As far as it reopening in May, they may have tentative dates but I can say the military is totally taking things day by day at this point, I'm sure MEPS is no different. I was working in recruiting up until a month ago, if he has a scheduled appointment, that's probably true, and if I were a betting man it will be cancelled. Also probably depends what level the authority to open/close MEPS has been delegated. I'm sure individual MEPS could reopen at different times at some point, but just as easily MEPS could opt to have all locations remain closed, modify operations, or fully open, or any and everything in between.
I'm in a TRADOC (training) environment right now and everything is being modified, changing, delayed, etc. Policy and procedure is being updated on an almost daily basis to deal with this thing. It's the same across the entire military.