Starting this week, the lifespan of new TLS certificates will be limited to 398 days, a little over a year, from the previous maximum certificate lifetime of 27 months (825 days).

Starting on September 1st, SSL/TLS certificates cannot be issued for longer than 13 months (397 days). This change was first announced by Apple, at the CA/Browser Forum Spring Face-to-Face event in Bratislava back in March.