If it is, you may want to see if there is an initial deployment job scheduled to run "reboot to production" after 30 seconds as the default initial deployment.
By default, once in PE, we should do absolutely NOTHING if there is no job assigned. I regularly have my PE environment stay open for days without rebooting just so I can test.
For new computers, if you set up Initial Deployment, you will be prompted with a menu of possible jobs to select from in Automation. This may be what you're looking for. Image Invoker is slightly different. New computers wll receive a menu of jobs as YOU create them and YOU select them on the Initial Deployment configuration page. As many jobs as you want. They'll be listed in a table, and the person sitting at the system can just select from one.
For existing computers manually booting to Automation, no such menu exists, until the next version 7.5 due Q4 late this year.
For Predefined computers, this doesn't work quite as well today, but in the next release, you can select the predefined computer from a list.
Anyway, that should be a decent start.