Time period for fulfilling the "Sunday obligation"
One issue remains, however: not a point on which I think McNamara is necessarily wrong, but rather, one for which the range of orthodox answers is, I suggest, wider than McNamara seems to realize. It regards the time period within which one may satisfy the Sunday obligation set out in 1983 CIC 1248.1: "A person who assists at a Mass celebrated anywhere in a Catholic rite either on the feast day itself or in the evening of the preceding day satisfies the obligation of participating in the Mass."
The leading British-Irish commentary on canon law reads as follows: "What is 'the evening of the previous day'? Despite the view of some commentators that this should be interpreted as beginning only at 1400 hours (2 pm) on that day, it is the firm view of this commentary that the evening of the previous day begins at midday (12 noon) on that day itself. In some dioceses there is a local regulation to the effect that the so-called vigil or anticipated Mass may not be celebrated before, say, 5 pm or 6 pm: this is normally for pastoral reasons, e.g. to facilitate weddings or funerals in the parish and other churches. Those regulations do not in any way concern the time prescribed for fulfilling the obligation to assist at Mass: thus, e.g., if . . . a person were to attend a nuptial Mass in the early afternoon on a Saturday, that person would thereby have fulfilled the [Sunday] obligation." (Fr.) Raymond Browne, Letter & Spirit (1995) 702, emphasis added. For a contrary view, see J. Huels, CLSA New Comm (2001) 1445.
For reasons that go beyond what I can present in a blog post, I hold the British-Irish position on this point, but, even if ours turned out to be minority view, it is, I suggest, more than sufficient (per 1983 CIC 14, among others) to defend the conscience of one who attends any Mass in a Catholic rite, beginning any time after 12 noon on Saturday but before midnight between Sunday and Monday, in fulfillment of one's Sunday obligation.
PS: Happy New Liturgical Year to my readers!