Bgrove wrote

T315 temperature sensor will not accept an offset other than the extremes of -18 F or 18F. Set for anything in between and it just goes to either extreme. Makes offset feature useless. Why is this happening?

  @Bgrove 

This doesn't seem right. What's the firmware version of your Tapo T315? And your Tapo app version?

Make sure your Tapo app is updated. You can try to delete and reinstall the app. Try to configure the offset on another phone, see if the issue remains. 

What's the model and operation system version of your phone?