Temp sensor inconsistency in Beestat views

I have multiple ecobee temperature sensors and put one in my attic to assess whether it’s adequately ventilated.

The problem is Beestat is reporting via sensor detail ~10 degF higher than the instantaneous value as reported by both Beestat and the native app. Is this an issue with the sensor, how the data is logged, Beestat, or something else?