Comment 8 for bug 1794588

We do have libraries that routinely place volume level holds on both On order items and items already in circulation. Generally it's when a library wants its own copies to fill the hold. This could be a patron's preference, or when the hold is for a homebound patron or book group. Having these holds cancel was problematic for us in the xul client and our libraries needed to learn to work around it.

We had lots of issues where opening an item in the unified editor and just making an edit to the call number would cancel the volume level holds.

Here's how I can picture it possibly working:

1. If the call number appearing in the unified editor is edited and has only a single item attached, the existing call number should be updated.

2. If the call number appearing in the unified editor is edited and has multiple items attached, a new call number could created and the item moved to the new call number.

In the second case, if there are volume holds on the original call number record, they could stay there, which is not perfect, but volume holds themselves are not perfect, and it would prevent them from cancelling.

There are more workflows to consider, but we need to make sure that the issues described on both bugs are handled. Volume holds shouldn't be silently cancelled and changing of call numbers for more items than intended by the editor should be prevented.