Blitzed Blacklist returning false positives

One older generation of the historical popular blacklist blitzed - that is also a legacy from the past - has slowly started to return false positives in our blacklist, for new mail servers that has taken over the old addresses from abusers. Hosts that are flagged "blitzed" must all be deleted. The amount of hosts affected is currently unknown, so there will be a bit of a rush for this issue.

Purging rules, based on comments, including DNSBL-48, so far:

Delete flagged with blitzed, with set dates (april 2016) where there are no content reference.
Since content references was initiated june-july, all host that are listed without a reference should be considered false alarms if they have a blitzed flag included.
Blitzed is very obsolete and urge to be removed from the system.