I thought there was explicite permission for this years ago, but I cannot find it. I do not do much service work and have refused to do this in the past, opting to add circuits that can be used all year. When I have seen this done, the #12 tap wires are shoved under the same lug as the #6 AL wire, and then either fused or ran to a small sub panel. At least they use gfci outlets! Where might I find the definitive answer to this seasonal, dual use, of a circuit? If it is legal, does anyone have a slick method of making this code compliant?