linux – On an Azure hosted RHEL instance, how could the Tomcat service get started as root when the .service file specifies a user?

We have 3 RHEL servers running in 3 different Azure regions.
All 3 have been running Tomcat, as a service, as the expected non-root user that is specified in the .service file, for months.

On the 25/26th May all 3 started running the tomcat service as root.
Restarting the service and systemctl demons-reload did not fix the problem.
Rebooting the box did fix the problem.

Any ideas how such a situation could occur?
Azure SNAFU or bad actor?
How worried should I be?