Have you done any significant changes to firmware or hardware recently? If the printer was working fine a week ago, something must have happened.

800 steps is correct for x64 microstepping and 16 teeth pulley.

I haven't seen any yet. There is a 3D model of Duet Wifi and Ethernet available on grabcad.com and they are same size as the Maestro with same mounting hole distance.

How does your bed height map look? G29 S1 should be a last line of your bed.g file if you want to use previously stored height map compensation before each print.

Have you done any significant changes to firmware or hardware recently? If the printer was working fine a week ago, something must have happened.

800 steps is correct for x64 microstepping and 16 teeth pulley.