What changes did CIQ team make for accelerometer sensor data?

I made an app JumpJump for rope skipping detection 2 years ago. it works fine most time.

Recently I got a lot  of reports about the  inaccuracy. But I didn't make any changes to my algorithm and code. It seems the values output by the accelerometer sensor are larger than before. What modifications has Garmin's team made?

Did you see similar problems in your projects working with accelerometer sensors?

I have to say , Garmin FW or  CIQ is really a buggy system.