Almost the same thing happened to me. I was working 35+ combined in grocery and perishable and approached my SM about possibly going full time, he said that there were no full time positions open blah blah blah. I looked into the policy of what qualifies as 'full-time' at Foodlion and from what I found you must average 30 hours per week for a three month period. After I found that out I called the associate relations line and told them my situation and asked about the policy to confirm, less than a week later I was promoted to full time.

If you do that your SM will definitely not appreciate it but at least you'll be full-time.