Frecciarossa 9508 apparently runs from Rome and Milan to Bardonecchia three times as week. The linked site cryptically states (in translation):
It does not run on Fridays, Saturdays and Sundays from 14 December to 30 January, from 2 February to 20 March and from 23 March to 29 March
It runs on Fridays, Saturdays and Sundays from December 14th to March 29th
It does not circulate on January 31st, February 1st, March 21st and March 22nd
If you add these up, the set of "runs" days seems to be identical to the set of "not runs" days, suggesting the service never operates!? Nevertheless, other sites like treniamo.it claims the train does run on Saturdays in December:
And I search for trains from Milan to Bardonecchia on the official Trenitalia site for a Saturday in December, FR9508 pops up:
However, it tells me to get off at Milan Porta Susa and board a Regionale service to Bardo! Repeating the search specifying "no changes" returns no results.
I am now thoroughly confused. Does FR9508 actually run in December? If yes, how can I book it all the way to Bardo?