Let's Encrypt Moves to 64-Day Certificates: Check Your Cron Jobs
From 10 February 2027, every certificate Let's Encrypt issues or renews will be valid for 64 days instead of 90. If your renewals are fully automated and your ACME client supports ARI (ACME Renewal Info), you probably have nothing to do. If a script renews certificates when they reach 60 or 80 days old, it needs fixing before then.
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