It's typically recommended not to feed during shed due to a brief phase of pretty much blindness, and the fact that the BP is already stressed out enough. After shed, the stress level is pretty much back to normal.

Here's some info from the Non-Breeding feeder FAQ:

http://www.ball-pythons.net/forums/s...ad.php?t=31105

5. Can I re-freeze a prey item that wasn’t eaten?

You can refreeze a fully thawed prey item if you do so within a short period of time. If the thawed item has been left overnight and uneaten, it is best to throw it away as it will have already started to decompose. Some refrozen prey items (especially pinks) will be more likely to have weakened belly skin so take care when re-using those. Separate and mark all refrozen prey items for next week's feeding. If they are unused again, dispose of them as repeated freezing will degrade the quality of your snake's food.