You'd think so, but the Chinese really have re-invented the meaning of the term 'close enough is good enough', and the testing regime (if any) might not extend beyond an accuracy of +/- 2C error margin wrt displayed temperature =)
Thing is, there's a few ways of achieving such calibration ;
*change the thermal coefficient factor in the firmware, of the algorithm that's doing the ADC measuring/reporting of the thermistor circuit, at testing time (or based on the tested performance of the unmarked batch of thermistors)
*install a 'shim' resistor in series with the thermistor, to make the thermistor temp/resistance curve closely match the firmware operations
If you hold that last thought for a moment, R67 (2K7) in series with the thermistor, may actually be that resistor shim...(or a current limiter...would be worth checking it's actual value with thermistor removed)
This is a thing, but not applicable here really due to the low temperatures/temp range involved ...tends to be a good solution when you need monitor high temperatures tho' ( >100C), like in boilers =)
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