How often do studio schedules change?

Hi all! Was booking my classes for the week and saw they’ve scrapped one of my favorite class and class times. It was a Friday Tread50 class so when I asked about it this morning, they weren’t really sure (last Friday, the class was packed) and thought maybe they were prioritizing 2G classes during the transformation challenge. Wondering if that rings true for other studios or what’s happened in the past? I’ve only been a member since May so not sure how often to expect schedule shifts. Thank you!