A few years ago we went through this exact situation.
We had the opportunity to move from the north to Florida, and found a house. Closed on our Florida house in July 4 years ago. Paid all utilities and taxes for the FL house while we prepared to move from another state.
Did the big move 6 months later.
My college student finished her semester up north in December, then took off one semester and worked in FL after our move while waiting for the application to UCF for the fall semester to be processed.
In order to prove residency for UCF, I had to provide closing documents on the house, paperwork that showed us paying the utilities, insurance and taxes, and our driver's licenses for FL (date didn't seem to matter on those, just that we had FL licenses). We were approved for residency, but I believe the cut-off was July 31 of the previous year to be accepted for residency.
If you have a college student that is already at a college in a different state, be prepared for them to repeat many of the classes they already completed once they transfer to UCF. My daughter had to repeat almost a year's worth of classes for her education major. If we had known the hoops she had to go through to continue her education in FL, she would have stayed at her previous college since she only had 3 more semesters to graduation. I don't know if all the majors at UCF are this way, but we were very surprised at how many repeat classes she had to take that UCF would not accept from her previous school.
Also, depending on the college, if are a college student at a non-Florida school, you might be surprised by how tough it is to get into the classes needed for the major at UCF. We found that some classes that were completed in one semester up north were spread out over 2 semesters at UCF, and those classes were not offered multiple times in a semester, but rather continued into the next semester. So, if you didn't take section 1 in fall semester, you had to wait until the next fall semester to take it. This was very surprising considering how large UCF is. It also explains why many students don't finish UCF in 4 years.
The other thing we noticed was that in-state tuition at UCF was much less than in-state tuition in our former state! However, housing for the college student was more expensive. Much more expensive. You pay one way or the other!
I am not sure how any of this will work regarding tuition while working at Disney. Maybe someone else will have more information in that regard.
Good luck, I hope you find what works best for your college student!