It sounds like a great idea to transition into the new job the way you describe...
Working a couple of shifts at the new place...and keeping the current job for now.
I had the same thought as D.S....
...eventually, you may find that you are really enjoying and doing well at the station...and you can have the option of getting more hours there, and leaving the boxing co.?
Finding balance of home, work and school is a challenge of course...but with your planning, coping skills and support, you can do very well at managing it all, I am sure.:)
Best wishes in whatever you decide! Keep us posted.:)
"Courage is not the abscence of fear, it is feeling afraid and doing it anyway!"
"Worrying does not empty tomorrow of its troubles...it empties today of its strength."
Corrie Ten Boom
Panic Syndrome recovery due to CBT