chrony sets source as offline at boot resulting in no clock synchronization

Issue

• Checking the chronyd.service unit status shows Source x.x.x.x offline after booting

  # journalctl -b -u chronyd.service
  -- Logs begin at ..., end at .... --
  ... systemd[1]: Starting NTP client/server...
  ... chronyd[654]: chronyd version 3.2 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +SECHASH +SIGND +ASYNCDNS +IPV6 +DEBUG)
  ... chronyd[654]: Frequency 13.776 +/- 2.124 ppm read from /var/lib/chrony/drift
  ... systemd[1]: Started NTP client/server.
  ... chronyd[654]: Source x.x.x.x offline
  

• chronyc activity reports sources are offline

  # chronyc activity
  200 OK
  0 sources online
  1 sources offline
  0 sources doing burst (return to online)
  0 sources doing burst (return to offline)
  0 sources with unknown address