The process of the skin actually coming off should take no more than a half hour or so, assuming proper humidity and other environmental conditions. This is when they are "shedding". It's the build up to that point that could take a week or more. That's when they are referred to as being "in shed".
Once they've shed the old skin, they will take food readily if they are healthy and have been eating. It just while they are in shed that they are less likely to eat. (And, as a side note, I've found that juvies will take food while in shed more readily than adults will).
Joel
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