I'm with merlotgran re buying another just in case the original doesn't pass the sniff test. If it smells ok cook and serve it up for the midwinter feast, maybe using the 2nd one at Easter 2018. If it does not smell ok then you've just got to bite the bullet and chuck it in the waste food bin, where it will at least feed the woms that can turn it into compost
Eglantine, I've never done a dry one yet, plenty of butter and bacon on top, proper stuffing made with sausage meat and chestnuts etc inside.
Blinko good freezer, loads of stars, but what would happen if I defrosted, cooked and sniffed, and found it lacking? What would we do then on that day?
I'd say, speaking technically (number of stars on freezer and all that), probably not. But speaking from a purely practical standpoint (my usual one) I'd make sure it was thoroughly defrosted, then thoroughly cooked through and if it still stood the smell test, I'd serve it....