Does anyone have any idea when the next firmware update is? Have all kinds of issues with drifting and motor warnings.

Suggest you contact DJI Support.  Cause we are hearing nothing about when next firmware update will be.
Besides, there are no guarantees next firmware update will address issues.

Can you not calibrate compass and IMU ?

I have tried that several times

I guess the focus is to the new Mavic 2, same with the Spark and now the Mavic Air. Updates are slow, to never I'afraid.