will UMD updates able to downgrade my PSP?

No, it will not work. If you click on it, it will say something like no need to upgrade anymore.
I wish you could downgrade like that, that would be awesome.

more easier, less painful, less stress, less THIS IS TAKING TOO LONG!

u can use a umd updater instead of making the UPDATE folder in the psp and putting EBOOT 1.5 in there. like downgrade without the eboot

yeah, but none of that works... well just have to wait a couple of weeks until fanjita comes out with his new eboots for the higher psp versions!