They check wheels every morning, and while there may have been a wheel that was close to be needing changed, they don't change it until it is necessary. First day of the season results in wheel changes too, it's just a constant thing that needs to be changed. 15-30 minutes TOPS to change most wheels.
Mamba went through 20 wheels in a matter of four days(?) when it was over 100 degrees in the summer a few years ago. Fourth of July weekend it only had one train and then it was closed because they were out of wheels until a delivery came in the next day. The problem for that coaster is it was designed with same wheel assembly as Steel Force and Wild Thing, but it runs faster, causing it to eat more wheels.
If it were wheel assembly, big difference, but a wheel is a non story.