Not possible since I didn't turn backup saves on. I work the next three days and I should be able to get some production going today when the kids are taking their nap. I guess since I already know where most everything is I can easily get things better set up in the beginning, maybe even bypass the top level farm and go straight to the permanent spot I had set up before. I'm just glad I had only just started on the projects I had planned so the only real progress I'll lose is the state of my military.
I'm going to try a few things first to make sure it's an unrecoverable save before starting over but I think that's what I'm looking at here.
EDIT: Take this suggestion with a grain of salt but I highly recommend scrapping this embark and starting the contest over once the merge comes out but with a shortened time frame for the windows users. There's enough issues with undead (my flying heads, this one elk bird that won't die) that having them being the primary enemy is counterproductive to the intent of the contest, which is to judge how well players adapt to the new features and how they can improve the overall DF experience. I understand you wanted the additional challenge there but that line of thinking, to me, stems from 40d where you sort of needed that extra layer of dangerousness because standard creatures just didn't cut it. However, after experiencing the primary aspect of the underground cavern, in that creatures constantly spawn off the edge, I don't feel the undead aspect is needed because there's more than enough challenge without adding in the constant threat of an unkillable monster. There's also enough of those to go around without zombifying everything.
Again, completely up to you since you're the administrator of this contest, but that is my suggestion.