Per request, we'll be making available to licensed users some extra queries to the SFDB database.
Right now, from the registered user area, we've added an option to search for specific IPs in the database. The results provided will show what kind of filters have caused an IP to be listed in the SFDB. Sample output is as follows:

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SFDB Database searches

Lookup an IP in the SFDB database:

Num of Referrals	Filter ID	Filter Description
9	10	EmailTO is not in AuthorizedTOEmail list
6	8	IP address is from a blacklisted country
5	16	Invalid sender domain MX record
2	18	IP blocked by honeypot entry