The Tier 3 blocklist comprises instances blocked by 2+ council instances. It looks like Oliphant stopped using that single-user instance as an input in May, which bumped woof.group off Tier 3. Oliphant also removed the unified-max blocklist (instances blocked by any council instance) around the same time.
We're still silenced by mastodon.art (nudes, maybe?) but they're the only council member still blocking woof.group. We're off the tier-3 blocklist for now.