Leah said that a familiar face/faces will show up as rebels in the last three issues. The only X-characters that are still unaccounted for in AOXM are:
Trinary, Firestar, Goldballs, No-Girl, Oya, Sprite, Triage, Monet, Nemesis, Prodigy, Rictor, Frenzy, Cypher, Thunderbird, Sage, Sprite, Tempus
Rictor is pretty much confirmed and we can scratch Monet off the list of potentials. Anyone else?