I’ve calibrated both of the soldering irons with the tips they have on them now to be 350ºC.
Please be careful if changing the temperature not to change the calibration as it’s a pain to have to keep coming down to change them, however both are now perfectly achieving their temperatures.
Whilst we’re on the topic:
For most jobs somewhere between 330ºC to 370ºC is perfectly fine for all types of solder, realistically 250-270ºC is adequate for many jobs.
People who need to crank up the temperature to 400ºC to get a bit more thermal capacity out of the iron, please remember to set it back down after as it wears out the heater, tips and thermocouple more rapidly, as well as potentially causing pads to delaminate for the next user.