They say they will still consider him gifted, he just won't receive any additional accomodations. We can reconvene a write a new GIEP if he needs more.
BTW, my daughter was accelerated several years ago yet she still had a GIEP which was worded much like Val suggested (same school district).
I am trying to find some other precedent or case law to bolster my position. The only helpful thing I found in the school's policy (which is very short) is this:

The district's gifted education program will provide: Gifted education that enables identified students to participate in acceleration and enrichment programs, and to receive services appropriate to their intellectual and academic abilities and needs.

I am hesitant to sign off on their plan because I fought for two years to get him identified.