I don't know about specific schools and their deadlines, but it certainly wouldn't hurt to quickly contact the schools which have 1 year MPHs. I know that the day for many people to decide on which school they would choose for their MPH was April 15 (I think), so I don't know if you can apply. But it certainly wouldn't hurt for you to start calling (you want to call, don't email) all the programs that offer 1 year MPHs, or just schools you're interested in going to. Some may be flexible, but you won't know until you ask.