The Debian ntp package (from ntp.org) is on the way out (https://lists.debian.org/debian-devel/2022/01/msg00172.html).

The original ntp client/server has been superseded by a few better options in the last years, e.g. chrony and ntpsec. Systemd also ships with a SNTP client which would probably be sufficient for our needs.

We should consider switching over to one of these implementations, which would be one fewer moving part in our infra.