At PSA, if you are not ready after 8 sessions, but are doing ok and are trying hard, you will get 2 additional sessions.

If you are at 8 sessions, have not been studying, and making the same mistakes that you made on session 1, you will likely be asked to go home. Especially if you have a bad attitude.

After that, you will likely have to meet with someone in management to determine what the problem is and if you will get more sessions.

I know that we had one instance that a sim was broken, and the students had a 4 day break right before the checkride. The training department didn't give them the option, but required that they have an additional 2 sessions before they would check them even though they were doing well. In another instance, an instructor got sick, and the students had 4 instructors in 8 sessions. They were not ready for the check ride after 8, and immediately were scheduled for 2 more with the same instructor that they had at the end. Consistency in training is important with both instructors and a regular schedule. If those things are messed up, it is not the students fault.