How often do MBPs update filtering rules?

MBPs update filtering rules continuously rather than on fixed schedules. Machine learning models retrain regularly, sometimes daily, incorporating new spam patterns, user feedback, and emerging threats. Rule based filters get updated whenever new attack vectors emerge.

Major policy changes follow longer timelines with advance notice. Gmail and Yahoo announced their 2024 bulk sender requirements months before enforcement began. But algorithmic tweaks happen constantly without announcement, which is why deliverability can shift unexpectedly.

The frequency varies by threat level. During active spam campaigns or phishing attacks, MBPs may push emergency updates within hours. Routine improvements roll out more gradually. This continuous evolution means senders must monitor deliverability consistently rather than assuming past performance guarantees future results.