AntiUpdate gets rid of the update icon available in the game menu when an UMD is inserted.
It patches the PSP RAM, so there's no flashing needed - ever.
The idea for AntiUpdate came from this tutorial by team FWi:
UMD games and homebrew work just fine, like nothing ever happened to your PSP.
The plugin has been tested and confirmed to work on 3.03OE-C, 3.10OE-A and A' and 2.71SE-C.
It shouldn't be dependent on firmware version at all as it searches the memory for the specific bytes
instead of relying in pure memory addresses.