Door to door shipping (USPS, etc.) is done for the season. December just has to many packages in transit to safely ship fish. Delays are almost a guarantee and it’s just not worth the risk to the fish to try and ship as the month goes on. I’ve also found that if the temps will be below 20 degrees (and they usually are at least at night through February around here) that door to door shipping just isn’t safe. Usually things don’t warm up enough until March for me to be able to offer door to door shipping again with the possible exception of a warm enough window that normally happens in January or February.
That said, as weather allows, I can still offer air cargo shipping on Southwest airlines for much of the winter.