I'm not sure if I'm posting this question in the right place, so please let me know if this isn't relevant for this section of the forum.

Every year during the winter season British Airways operate services to Rovaniemi (RVN) and Kittila (KTT) with callsign like XMS001, XMS5BZ and XMS10. The actual callsign is "Santa 001, Santa 5BZ, etc."
I have noticed that Flightradar isn't showing the flight number or the flight itself on the arrival/departure list for these airports. I'm wondering what the reason for this is.
During the winter season, it's regularly done every day, and I don't see a reason why these flight wouldn't be on the schedules.
It's also not possible to playback these flights by searching the callsigns used, and it's only possible if you know the registration that was used for that flight. Why is this?

Thanks for your help!


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