But as yet, the option once available for this is gone.
By design, the product will give you a 3 second timeout until you actually assign a job to it. Consider it this way. There are essentially 3 states for the PXE selection menu:
A = 3 second delay to press F8
B = no delay - boot to prod
C = no delay - boot to automation.
When the PXE services are started, all computers are set to A. This is the default.
When you assign any job with a "reboot to" task, the computer is set to either B or C.
The computers are only changed from their current setting when another task is sent to it. Thus, once on B or C, they never return to A until the services are reset.
AND, as mentioned, there is no setting currently in the console to control if this is ever reset, or to increase/decrease that F8-timeout.