See Using Your Assigned Administrative Rights in Securing Users and Processes in Oracle Solaris 11.4.
$ date mmddHHMM[[cc]yy]
The following example shows how to use the date command to manually set the date and time of a system.
# date Monday, September 13. 2010 02:00:16 PM MDT # date 0921173404 Thu Sep 17:34:34 MST 2010