POS terminals lost all pending jobs

[Jeff Burton]

On a couple of POS terminals I have setup, it appears that all  
pending jobs in the jobsandbox are gone.  In addition to my push and  
pull are the standards (which I assume come from seed data) for  
cleaning and retrying.  One thing that was done to these systems was  
changing their timezones to be 2 hours later (moving east).  Anyone  
run into anything like this before?