this seems possible to avoid as an issue without needing IP certs by having the configuration supply both an IP and a hostname, with the hostname used for the TLS validation.
Yes, that is absolutely possible, but doesn't mean that will be the default. I commented recently [0] about Ubuntu's decision to have only NTS enabled (via domain) by default on 25.10. It begs the question how system time can be set if the initial time is outside of the cert's validity time-frame. I didn't look, but perhaps Chrony would still use the local network's published NTP servers.
