Company issued devices usually point to a Time Server which is accessible anywhere across the globe. In my situation the company i work for was not the case.
Users were taking leave over the Christmas period only to lose sync with the Time Server (which was only internal accessible). To rectify this, we had to create a script which points to a internal NTP server failing that, it should fall over to a external or public facing NTP.
The below script was used to get this remotely configured for our business.
#This script has been created to assign 2 NTP Servers on macOS Clients
#Internal and External NTP Servers as listed below
#Primary Time server for Company Macs
#Secondary Time server for Company Macs outside of Corporate Network
# Set the primary network server with systemsetup -setnetworktimeserver
# Using this command will clear /etc/ntp.conf of existing entries and
# add the primary time server as the first line.
/usr/sbin/systemsetup -setnetworktimeserver $TimeServer1
# Add the secondary time server as the second line in /etc/ntp.conf
echo “server $TimeServer2” >> /etc/ntp.conf