Depends on the company. In Virgin, there are no fATPLs. An FO becomes SFO after 2 years' satisfactory service. I believe that in BA it's considerably longer. In both airlines, pay is incremented annually whether you are an FO or an SFO, and - at least in Virgin - the step from FO to SFO is no greater than any other increment. 'Perks' tend to be length-of-service related, rather than rank, though you can expect a captaincy to accrue more perks than FO/SFO.
Incidentally, PPJN is nothing to do with Pprune.