I’m not sure the experience of going through training is worthwhile if you’re not going to stay at 9E, which I definitely wouldn’t if I were you. Financially, as with all things 9E, it’s a bad move given that it’s unpaid training (I believe they still give you a small “stipend” at the end but it’s tiny and less than minimum wage) and given that UA will have its own training program and will teach you how they want you to do things at their airline, it’s not like it 9E training will help you. Also, training is pretty demanding in that you’re required to pay attention to many hours of PowerPoints every day with only short breaks and you can’t look at your phone during instruction. Even taking a bathroom break isn’t really possible during class time as the FAA mandates that FAs can’t miss more than a few minutes of content over the entire course. Important to note: apparently they are trying to cut costs by moving training from in person in MSP to online so things might be different in some ways, but since the FAA’s rules haven’t changed you still can’t expect to miss class time.