You can carefully peel the mat back but you may damage it.
The problem with having the probe under the mat instead of between the mat and the glass is that cold air (a/c) can make the temperatures fluctuate more.
Oh, I see...
So I keep seeing online that there are different suggested heat ranges for the warm, cool spots, and I'mstill really confused as to which rages are better. So as a hatching I should set up for 76-78 on the cool end, and 86-88 on the hot end?