SIP 408 Timeout on BYOC Trunks during Peak Hours

Could use a hand troubleshooting this recurring SIP 408 Request Timeout on our 15 BYOC trunks in Asia/Singapore.

Context:

  • Environment: Genesys Cloud v2.1
  • Trunks: 15 BYOC across APAC
  • Issue: Secondary trunks drop registrations with 408 errors during high-volume failover events.

Question:
Why are the secondary BYOC trunks consistently timing out after the recent SBC firmware update, while primary trunks remain stable?