Windows Task Scheduler now saves the user as a SID (security identifier - a bunch of numbers with hypens in it) instead of the "DOMAIN\USERNAME" and in my case it turns out that there was a new restrictive security privilege called SeDelegateSessionUserImpersonatePrivilege that is set to disabled.
Removing this privilege fixes my issue with the Task Scheduler in that it would run a task, but not as the user that was set to "Run as".
Windows Task Scheduler now saves the user as a SID (security identifier - a bunch of numbers with hypens in it) instead of the "DOMAIN\USERNAME" and in my case it turns out that there was a new restrictive security privilege called SeDelegateSessionUserImpersonatePrivilege that is set to disabled.
Removing this privilege fixes my issue with the Task Scheduler in that it would run a task, but not as the user that was set to "Run as".