SDK? Rearranging images when sort set to "Custom Order" causes errors

This issue shows up in a published service plugin but it can also be duplicated somewhat in a normal collection. The same error messages print in a normal collection when reordering images.

Issue: LR Classic v11.2 rearranging images in "Custom Order" causes errors
LR Classic: v11.2, Build [202201281441-a5b5f472]
OS: Windows 10 Pro, v21H2, Build 19044.1526
Step 1: Create published collection which contains some images

Step 2: Publish images to service

Step 3: Change sort order to "Custom Order"

Step 4: Drag an image to a new location

Expected Result: No errors

Actual Result: 120 error messages print to debug console and LR is unstable for a bit, sometimes publish service is non-responsive for up to 5 minutes. Sometimes it recovers and sometimes I have to restart LR.

BTW, I tried two previous times to post this where I cut and pasted the error messages as part of the post body and both times my post was marked as spam... So, I've attached a screenshot of the first few of the 220 error messages