The stale file was apparently left by /etc/dhcp/dhclient-exit-hooks.d/ntp. Since this dhclient script updates the ntp.conf.dhcp file when a new NTP server is advertised via DHCP, it should be OK to always use the most recent file between /var/lib/ntp/ntp.conf.dhcp and /etc/ntp.conf.
The attached patch changes the initscript to use /var/lib/ntp/ntp.conf.dhcp only if it is newer than /etc/ntp.conf.
The stale file was apparently left by /etc/dhcp/ dhclient- exit-hooks. d/ntp. Since this dhclient script updates the ntp.conf.dhcp file when a new NTP server is advertised via DHCP, it should be OK to always use the most recent file between /var/lib/ ntp/ntp. conf.dhcp and /etc/ntp.conf.
The attached patch changes the initscript to use /var/lib/ ntp/ntp. conf.dhcp only if it is newer than /etc/ntp.conf.