i currently have an iphone 3gs with 3.1.2 jailbroken. it was manufactured in week 29 of last year according to my serial number. does that mean i have the old boot rom/non MC-model? i know 3.1.3 has no new features. the only reason i have to update is because my cydia/apt is screwed up and the only way to fix it is to restore. itunes will not let me restore my 3.1.2 without updating (yes, i tried the shift/option button thing). i just want to know if i upgrade to 3.1.3, will i be able to jailbreak with snowbreeze? p.s. i know i can upgrade and downgrade using saurik's method, but that's just too much work.