It seems to me that the question about communion on Christmas would make for a good dubium, even in the Usus Antiquior. It’s really quite an interesting question.
Christmas is the only day of the year where, in the Latin Church, there are traditionally 3 separate Masses, and every priest has the right to celebrate all three without need for special permission (and I believe this is still true even with the Novus Ordo). It often happened (and occasionally still does in the Usus Antiquior, at least) that priests would offer the first 2 Masses back-to-back (Dominus Dixit at midnight & Lux Fulgebit, aka “Mass at Dawn” immediately following it) so the same congregation was normally there. The 3rd Mass of Christmas (Puer Natus) is sub-titled “Mass During the Day” and was always offered after sunrise.
An argument could be made that, although there is only one “obligation” on the part of the faithful and any one of the 3 Masses of Christmas fulfills that obligation, (and I gather that in the Novus Ordo the Mass of the Vigil of Christmas does the same), since a priest is not bound by the normal rules regarding bination provided he offers the three Masses according to the Missal, the faithful may likewise not be bound by Canon 917 provided they assist at the Three Masses OF Christmas (not merely 3 Masses on Christmas).
This may have been submitted as dubium at some point, and if so, I’d love to see the formal response from the SCR (or the CDWDS as I think it’s now called).