I think the most important thing about taking this change of commitments is that you are doing it with a respectable and mature attitude. It sounds like this was a well-thought out decision, made out of concern for both your own well-being and your team's. You definitly earned my respect, though I don't know you
Keep in mind that FIRST is supposed to prepare you for a focused career in your subject of interst, and help you manage your time and resources effectively. You need this cash, you're earning it. You may want to talk to your team leader just to clarify your schedule, but like Jake said, you can commit to two activities without giving up on either.
I wish you the best of luck with managing both robotics and your apprenticeship!
- Genia