It is possible to withdraw an item that has an outstanding branch transfer, leaving an uncompleted branch transfer record. To reproduce: 1) Check in an item whose home branch is not the current branch 2) Confirm the transfer 3) Set the item to 'withdrawn' 4) Check the branch transfers table -- the branch transfer will still exist, even though the item is withdrawn (i.e. not in circulation). See Also: 12362 Branch transfer records orphaned on cancelled holds
I think this raises some of the same questions as Bug 12362 in terms of trying to understand what might be physically happening to items which have an open transfer. I think it's also important to consider the fact that Koha has, as far as I know, no official definition of what 'withdrawn' should mean in functional terms.