I'm sorry it took so long to reply. I am looking for the best path to follow. Some say, evaluate your risks first. determine legislation then significance of risks and there is a table to follow from there. Others have 'packets' that start with understanding the Context of the Organization etc. I know everyone will accomplish the same task differently, however a straight line usually works pretty well for me. ie. if I want to get somewhere, I look at a map, decide the route and go. I have been trained, however am still a bit confused. The plant I am working in has received a 99.2% on it's most recent GMP audit, so I know that we are doing many things right, I just need to understand this audit format more clearly.
I think you are over-simplifying the distinctions.
IMO fssc22000 is a different world as compared to a typical GMP Standard. (GMP simply gets an appended mention within the definition of PRP although this is not to bely the critical importance of such programs).
The forum often gets queries on how easy is it to transition from, just as an example, AIB/GMP Certificate to one for a GFSI-recognised Standard. It's often not.
In UK, an "intermediate" category as exampled by Salsa exists which attempts to act as a "stepping-stone" for GFSI.
As per previous Post, A Gap Analysis helps to illustrate the nominal differences.