It does vary from state to state, in the real liberal states you can pretty much almost stay forever (about 8mo) but in more conservative states it may be as little as 30 day's. There are things going on in the court system now to let deadbeats stay in their homes a very long time without paying a cent, they are blaming that on the deed recorders or Morgage managers not dotting the I's and crossing the T's.
Cross your fingers you're in a liberal state I guess. Good idea to get some advice from someone that knows. If they get an eviction the sheriff shows up and throws your stuff out. They usually get the local jail convicts to take it out of your house and put it on the curb. From there it's up for grabs. I would stay as long as you can. The banks do a real crummy job of working with you. With all the bailouts and no interest loans they have been getting they deserve whatever happens to them.
The states that are extending the time are doing so because the lenders didn't follow proper procedures on foreclosures. If the borrower has to follow a contract it is only fair that the lender should have to also. I don't see why the lenders can't work with people. They're going to end up losing a lot more through a foreclosure than taking a smaller payment or putting past due payments on the end of the loan or something like that.