Help downgrading

So ive been happily sitting on 3.55 on my CECHC03 and my nephew wanted to play uncharted 3 so he pops in the disc, while im out at work i hasten to add, and of course it says it needs updating he duly presses the x button :-O i now have a Phat backwards compatible PS3 on OFW 3.72. :rant:

I have looked around and im really confused as to what my options are for downgrading one thread seems to suggest i can downgrade in recovery using a downgrade pup other threads seem to suggest i have to have a hardware flash.

Can someone please untangle my confusion do I have to have a flasher downgrade? and if so is there anyone in manchester in the UK who can do it for me please?

thanks

adi