geordie, winter will be challenging but summer shouldn't be too bad. I think the worst case scenario is that you will have to nurse the pupae a little, but otherwise summer should be easy.
I would keep returning any light colored grubs from the collection bucket back into the BioPod. They may be inactive because they're getting ready to shed their skin and maybe they have another stage of active feeding to go. It's not unusual for immature larvae to migrate out of the unit, especially if it gets a little warm.
With your climate you probably don't have a local BSF population. For the record I've shown many native Georgians their first BSF, this is BSF country. The reason for that is the life cycle and habits of these critters. They just don't go around people normally and the adults live such a short time. I'm sure many people picture swarms of BSF around a BioPod but it just isn't true.
