KOMO has been doing the KPLZ simulcast since KPLZ started doing Christmas a few years ago. I too found An American Christmas last night, not sure how long it is. One thing I noticed was that the simulcast was longer than usual. Usually when I get up Christmas morning, KOMO is back to its own programming, but they were still in simulcast mode this morning. KXXO seemed to go late this year, but was playing some pretty unusual songs earlier.