Modern Net::SSLeay docs indicate this should be possible. Basically we need to set the extension to request the staple, and then check afterwards that it's a valid staple, with some configurable timing constraints on the NotBefore/NotAfter window, as well as validity of the stapling cert, etc. Given expected refresh behaviors, we probably want to be able to WARN if NotBefore gets old (e.g. >75m), and then CRIT if NotAfter is less than X hours from expiry.