One of the odder American adaptations to the liturgical calendar is the anticipation (or postponement) of Epiphany on the previous (or following) Sunday. Epiphany, the oldest festival of the Christmas season, is still celebrated in the universal calendar on its ancient and traditional date, January 6 - in some countries (e.g., Italy) still observed as a public holiday. But in the US Epiphany is moved to the Sunday after January 1 - presumably to facilitate more widespread popular awareness of it. Of course, this wreaks havoc with the symbolism of the ancient date, not to mention the popular Christmas carol, The 12 Days of Christmas, which this year in the United States are in effect reduced to nine!
Of course, there is nothing biblical about the 12 days of Christmas, and both December 25 and January 6 were originally pagan festivals. In that sense, the alteration of the calendar may seem less offensive than the widespread transfer of Ascension Thursday to the following Sunday, in spite of the scriptural basis in the Acts of the Apostles for the traditional date of the feast, 40 days after Easter. Still, when we transfer feasts for the sake of convenience, it is hard not to suspect that they are diminished in some way.
Twenty-two years ago, I was in London on Epiphany - then still celebrated there as a holyday of obligation and on its traditional date. We had attended Sunday Mass at the London Oratory and New Year's Day Mass at Westminster Cathedral - both beautiful experiences of solemn liturgy with wonderful music. But on Epiphany, which was a holyday but not a holiday, we went to an early morning Mass in a small, working-class parish. While not quite as grand as the Masses we had attended in those other more prominent churches, the early morning Epiphany Mass we attended featured by far the best homily of the three - an experience we probably would never have had if Epiphany had been transferred to a Sunday!