jcrack,
It is very hard to get hired on full time after peak. There are contractual constraints as far as the ratio of 'outside' hires to 'inside' hires. You are considered an 'outside' hire. The chances really depend on whether or not your area is a 'growth' area. If it is, you may stand a slight chance.
If you are working during peak, make sure you have study, comfortable footwear (i used Tingleys for overwear- had snow to deal with), pack a good lunch, and maybe a thermos of some nice warm soup.
Work briskly, but safely. Watch where you put your feet, slips and falls are one of the the most common injuries in the winter. Have a good flashlight. I recommend wearing a headlamp, it leaves your hands free.
Hopefully the area where you will delivering has an easy numbering system for addresses. Learn even from odd and whether the numbers jump by 5's 8's 10's or whatever. If you finish early, call in an volunteer to help others, always ask the boss if there is anything else you can do. After you finish, ask if they need help unloading the trucks.
Use your eyes and ears more than your mouth. Find out who is running things and suck up to him/her. If you don't get hired back, use your experience to try and get in at FDX or DHL, the work will be easier.
Good luck, keep us posted, and remember there are no stupid questions, only stupid answers!
PS- Josh, crack is probably not the best last name you can choose
!