PEI crazing

[bryand]

I am using Prima ASA+ filament on an Ender 5 Pro. I have been getting good prints with a 0.4 mm nozzle temp of 245°C and a bed temp of 85°C.
I am using a PEI bed which works fine, especially after fettling it with 800-grit wet&dry paper, used wet.
However this morning I noticed a feathery crazing on the build plate denoting where the corners of the heater element are on the underside. The surface of the build plate is smooth.
PEI_crazing by Bryan Dawson, on Flickr

Is this just the result of the high bed temperatures? What will happen if I continue to use the PEI plate at 85°C?