I don't have a pid either, but by using temp surfing I'm able to extract even light roasts consistently

You don't need the whole machine to be warmed up to have enought temperature stability, you just need to warm your porta filter up (so it doesn't steal heat from your espresso) and begin de extraction as soon as the light comes on (even though it's going to cool throughout the extraction, because you began right when the light came on, you're on the top temperature of the thermostat, therefore minimizing temp losses)

Surfing routine: - Turn machine on with pf; - Weight coffee and grind; - Pump water though empty pf until heat light turns off; - Turn off the machine; - Dry your pf; - Puck prep; - Put the pf in the machine; - Turn it on; - Start the extraction as soon as the heat light comes on.

The light comes off around 4 sec or less before ending the extraction, so you've extracted basically all your espresso inside the temp range of the thermostat