There is a workaround to build part-time schedules. In the "new schedule" screen, you can load a native part-time schedule and modify it. You can then save it and it will be a part-time schedule that can be saved/loaded for part-time clubs.
I've built the 5 schedules from @ZaZ as part-time...
For me, it's a big step (back) in the right direction. It feels more like a finished product than 26 was. Still not the best opus, but the terrible years might be behind us!
I can't say how or why exactly, but FM26 was the first FM in 15 years where I had absolutely no sense of immersion. FM27...