For the blues rock band we are going to do Merry Christmas Everybody because although it's not bluesy it's musically interesting and it fits our sound. We're also going to do Canned Heat's Christmas Blues which feels up-tempo even though it's a bit of a plod and plenty of room top extemporise :
Covers band it's Slade (nice, two birds etc.) and oddly they have chosen to add Wake me Up by Avicii which has apparently been described as a 'summer anthem'.
A bit like September, although that's probably the ultimate 'more than the sum of its parts' song!