Do you remember when she last shed? While feeding heavy causes growth, and growth causes shedding, my girls going into season have a shed almost right at the same they start cool seeking (I'd say usually within a week of each other) and then don't shed again till after ovulation. There are exceptions, but I'd say they stick to that pattern about 95% of the time.
If it really is building follicles, she is likely to be cool seeking for 2-3 months vs a few days to a couple weeks. If she is near her bowl for a couple weeks and then sheds and returns to the warm side, she probably was just trying to soak up extra humidity for an intense shed after a lot of growth.