Y-axis movement error
octopus8 recommended doing a series of tests to determine the cause of the problem.
I started with moving the bed by hand (remember to have machine off or choose &quot;Disable steppers&quot; from &quot;Prepare&quot; menu) and the movement was relatively smooth with some resistance, the same as when moving the X-axis.  If you move very slowly you can feel slight, small &quot;steps&quot;, this is normal. The movement was consistent across the range of movement.
Since this did not indicate a problem, I moved on to checking the drive belt and the bearing wheels.  The belt had a small amount of slack which I tightened.  Several of the wheels under the bed slipped against the rail they run along.  I tightened these.  This improved the movement of a couple of them but a couple still slipped a bit.
After this I did not have the problem anymore.  For 10+ prints over a week or so, there was no incorrect Y-axis movement and &quot;Auto home&quot; always worked. Nevertheless I continued with the next test suggestion which was to send some simple gcode to the printer via USB.  I used both Ultimaker Cura 4.8.0's Monitor mode as well as [sending the commands from the linux terminal][1].  I sent the commands
G28 
G0 F&lt;speed&gt; 
G0 X200 Y0 
G0 X200 Y200 
G0 X0 Y200 
G0 X0 Y0

with values of 900,1800,2700,3600 and 4500 for  and everytime the print head returned to the same place.
This is evidence that the tightening of the belt and wheels likely fixed the problem.
[1]: How to directly send G-code to printer from a Linux terminal?