Investigate what happens when mixing standard and partial updates

[SarahFrench]

What kind of contribution is this issue about?

Other (specify in details)

Details

This issue is blocked by issues changing the update verb for the given field: #17832

Someone needs to investigate if the problem can be solved by changing to using 2x partial updates, or if a change to templates is required.

Also, possibly as separate ticket, alerting to identify this issue would be helpful to contributors.

References

#17832