It's not that it was shortened, it sounds like she may have negotiated for that number of episodes. Most likely so she could pursue other projects. Guggenheim mentioned in the interview that they've had to write around the limited number of episodes.

The reason Thea has been so absent lately is that she's only contracted to do 14/23 episodes for the season so the episodes she can appear in are limited. Marc Guggenheim confirmed it recently in an interview.

From what I understand from the context of the show, Gems that are bubbled are essentially in suspended animation. Bismuth had no sense of the passage of time while she was bubbled and didn't claim that she had suffered or felt any pain while in that state. Actually, of all the Crystal Gems, Peridot has been poofed…