Originally Posted by diesel701
Your first (A) has no evidence. I've unpacked and packed an original firmware and the PS3 with 4.25 accepted it. So we can repack PUPs for 3.56+..
Then i stand corrected. I don't know what is stopping us from modding lv2 (assuming FAT ps3/old BL) and creating a 'downgrade' PUP then. I guess some experimenting is required in this area. Perhaps version numbers are checked, and not all checks are known at this time? (lv0 has an internal version number, perhaps this is checked?)