Gepc stands for Gloss-Enhancing Paintwork Cleanser. It is a mild polish from P21S. I copied a brief description of it below from CMA:
A companion the new P21S Paste Wax, P21S Gloss-enhancing Paintwork Cleanser is an equally easy-to-apply pure polish. It improves surface gloss by removing old wax, minor spotting and swirl lines before waxing. The thick, rich, cream wipes on and buffs off with an absolute minimum of effort. Now you can spend more time polishing your backswing!
I thought it had been added to the acronyms list.
:nixweiss
