Confused about when 3yr clock starts ticking with foreclosure

[ssmdem]

If we're surrendering our home during bankruptcy, we intend on stopping payments immediately, when does that 3yr (or 2yr) time clock start ticking as far as when we could get another mortgage? I know the property has to be out of our name, but is in when it reverts back to the bank after the sheriff's sale, or is it when the bank finally gets around to selling it to someone else?

Also, somewhat confused on the 2yr/3yr thing too. Ours is not an FHA loan. Is the 3yr just for those - or is it any mortgage?