User blog comment:CzechOut/Welcoming back the banned/@comment-366087-20131225115511/@comment-188432-20131225170255

Man does it ever clear IP addys! If you've got a lot of admins on your site, you don't always know how they're blocking. And you'll probably discover that at least some admins — and maybe even yourself! — have blocked IPs indefinitiely.

Took the better part of a work day to get rid of the hundreds of IP blocks at Tardis.