Christmas Mash-up No.3

This time I have mixed "O, Christmas Tree" with "Hark! The Herald Angel's Sing!"  I included three stanzas of each Carol and each occurrence of each stanza is set differently with the final one being a bit polytonal.  Also, this time the mash-up is accompanied by a brass octet instead of strings.  And the choir is a SMAATTBB 8-part choir.  Thanks for listening and I hope you had a Merry Christmas and that your New Year will be a happy one!  I'd appreciate any comments, suggestions, critiques or observations!

Nice layering of the different melodies! At one point I wasn't sure which song I was listening to because you blended them together so seamlessly. Nice change-up of the harmony towards the end.