downgrade ps3 rebug 4.84

I've recently bought a Cfw 4.84 rebug dex and in attempts to gain acces to online functions i want to upgrade to latest ofw, however ive heard contradicting things about dowgrading to 3.55 cfw first or useing qa flags and doing it straight from xmb, all my attempts to get to 3.55 cfw or 3.55 ofw...