I didn't think there was a PA pension increment for PA in the first 5 years under AFPS75. I think the theory was (didn't last long though did it!) that you'd had an FRI to keep you sweet for the first 5 years.
From what I remember, having done the 5 years (as you seem to plan to do) the increment then trips in at a level that makes up the daily increment over the 5 year period. For a PA Sqn Ldr it is worth approx 1k (50ish p per day), while for Flt Lts it is more like 1.6k. I'm surprised you didn't find the figures in AP3392 Vol2. I've got a note here that they were in Leaflet 2002 Annex B.