Datacenter/hosting-IP-flagged signups are a strong enough spam signal on
their own that a full day of grace was mostly just delaying an inevitable
suspend. Cron cadence tightened from hourly to every 10 minutes so real
latency stays close to the new 1h window.
Watches every account flagged by IP-scrutiny or email-domain scrutiny at
signup and, once it goes live, records a baseline post/follow count. A
scheduled sweep (app/suspicious_sweep.py, run via cron on admin.yttrx.com)
suspends any watch past SUSPICIOUS_GRACE_HOURS with zero new posts and
zero new follows since that baseline; any activity clears the watch.
Works whether yttrx is open-registration or requires moderator approval,
since the watch starts at whichever event actually makes the account live
(account.created vs account.approved), same dual handling the welcome flow
already uses. Needs ABUSE_BOT_TOKEN re-minted with admin:read:accounts.