I went on PCQI training in the UK and the way the UK approach HACCP (which I believe is slightly different from the US) means that virtually no changes are needed for FSMA compliance. All I did was take the hazards FSMA identified and said which hazard category I considered them in my HACCP plan and I also put more information in around my prerequisites (they were already specific but the stuff I put in was around what monitoring and / or verification there was for each) which, honestly, I should have already done for HACCP compliance anyway.
The training was painful by the way. About 10 Level 4 HACCP specialists in the room, all with 10 years experience plus of writing HACCP plans were taken through what felt like Level 1 HACCP over a three day training course. The slides were not allowed to be changed by the FDA and all the worked examples were just that, examples. There is no strict method by which you have to record your plan. One lady was hilarious, she kept putting her hand up and saying:
"Do you have to lay it out this way?"
"So I've done it this way, is that ok?"
"So I don't have to change anything?"
Sits back in chair, folds arms, blows out cheeks and looks like thunder at the biggest waste of 3 days.