Ars Technica: Let’s Encrypt cuts certificate lifetimes to 64 days starting February 2027

This move shook industry norms at the time, but by limiting the certificate lifetime, the certs are less likely to cause damage if compromised or assigned in error. The move down to 64 days continues this logic, and the lifespans will only continue to get shorter as time goes on, with 45-day defaults planned to follow in 2028.