Also, depending on where your draw off box is, front or back of the pan, can have an impact. On my CDL 2x6 the draw off is in the front. Poor placement if you ask me because there's a lot more heat in the middle and back partition. I get syrup back there a lot before the front section until the gradient really picks up.

So, when I draw I get under-dense syrup for the temp followed by a spike in temp with over-dense. After a longer boil it all evens out.