Renewed my LetsEncrypt Certs as ECDSA this time around, and subsequently found out The Plex Server is my only service that can’t use ECDSA certs, had to create a special RSA one jsut for plex.
Should be noted the Clients (Roku, XboxOne, PS3/4, Xbox360) seem to have no problem as they are connecting via TLS via Cloudflare which uses ECDSA certs.