when an entry from the lld rule input is gone, we delete the items and associated entities (triggers, graphs etc). in some cases, it is known that something changed the name - maybe network interface or database.
a database might have lots and lots of items, and deleting/recreating them would lose all the history (also events, alerts etc).
it would be great to be able to specify "old" and "new" values, telling zabbix to update all created entities.

somewhat similar to ZBXNEXT-3059 (specifying "old" key in xml import)