12:09 PM
@Derpy You're jumping to conclusions. There are so many other ponies who could change. The Cutie mark crusaders could get a second cutie mark, or grow to their adult form. Apple Bloom could decide not to wear the bow anymore, or Spike or Owiliscous could finally start to wear the bow Rarity made them. Scootaloo could learn to fly, which could come with any number of external signs, such as a pair of airplane wings with jet engines, plus an airplane tail for stability.
Pinkie Pie could decide she prefers the seapony form to the original quadruped. That won't happen to other ponies because they'd have a problem moving the land, but I don't think it would bother Pinkie. Twilight Sparkle could grow a second pair of wings because she's DOUBLE PRINCESS like Pinkie said in S4, or she could start wearing her crown like Rarity suggested. Diamond Tiara could get a bigger tiara.
Princess Luna could finally regenerate from the weakness caused by the banishment on the moon and regain his large body, as large as Princess Celestia. Rarity could decide that the ugly hair from S7 E19 suits her after all.
Cranky could finally grow her own hair instead of a wig, with some magical help from Zecora.
Or Rainbow Dash could finally have enough of the Wonderbolts and join the Shadowbolts. The dark costume would be nice.