An 8G iPod touch 3rd Gen (or 2nd Gen MC model, I guess?) is currently jailbroken on 3.1.2 with SHSH backed up on Cydia. It's tethered via blackra1n. Is it possible to upgrade to 4.0, without having jailbroken on 4.0 yet (meaning no backed up SHSH for that specific firmware), now that 4.1 is released? I'm aware that Apple isn't still signing 4.0. I'm guessing that it's not. Apologies if this is already made clear elsewhere. I just needed a quick clarification.