I was able to catch the programme on Christmas Eve. Unfortunately, I was unable to find Sunny 106.3 on my Internet radio after all. I don't know what happened there because I am absolutely sure I've heard Christmas Across The Lands on that radio station in previous years.
Christmas FM (out of Dublin, Ireland) is where I once again caught it. As usual, the station aired it from 6PM on Christmas Eve.
I was also able to listen to some of the programme - on Christmas FM - last night before bed. When my radio's battery died, I thought 'there it goes for another year'.
But I was wrong.
After waking up this morning, I scanned other stations on my presets I have stored on my older Internet radio and have found a station that is playing Christmas Across The Lands for 24 hours.
WCSF 88.7FM - a station ran by the University of Saint Francis in Joliet, Illinois - is where you can find the programme for the next few hours.