can only speak for our program, but yeah you are probably safe. I'd imagine it's similar at most places (our coordinators have no problem working on weekends, but going through applications is neither expected of them nor something I've really seen them do)
I still glance every few hours. I got invite after 8pm one night (it was from east coast, too). Ever since that I have felt no time is safe to go off the grid. However, 1)i'm IMG. and 2) I only have 3 interviews. I cannot afford to make any mistakes at all. If you have more security, I wouldn't sweat it.