Starting this year, a lot of students applied for GPR/AEGD and it was very competetive. Allmost all of the good programs (to me that includes prog with exposure in Implants, Perio Surgery, and Endo) were filled by the time Match date rolled around. Pograms conduct interviews before their dedlines, which 99% have before end of Dec.
After Match date, there are a lot of programs which will have spots open for you to Post Match (a lot of these progams are in NY). Which they try to fill asap after Match, so to land at a good prog out of the Post Match, be ready to call these programs the day of Match. It is rarely that a good program would have spots open after Match, but you never know.
So goodluck and hopefully it works out for you!