There was a discussion a little earlier concerning the feasts transferred due to occurrence with Sundays or Privileged Octaves like Holy Week and Easter Week. Here’s a brief historical note which some may find of interest.

While browsing through the Ordinale Sarum for Primum E (one of the earliest possible dates for Easter) I noted the following entries:

• After March 16th (Palm Sunday) it states: “Festa Sanctorum Edwardi, Cuthberti, et Benedicti differantur vsque ad eorum translationes” (The feasts of Sts Edward [3/18], Cuthbert [3/20], and Benedict [3/21] should be delayed until [the feast of their] their translations [which celebrate the moving of their relics and which fall respectively on 6/20, 9/4, and 7/11]). (St Joseph isn’t on March 19th in the old Sarum kalendar—he won’t show up for a while…)
• After March 23rd (Easter Sunday) it states: “Festum Annunciationis differatur in terciam feriam post octaua Pasce.” (The Feast of the Annunciation should be delayed until Tuesday after the Octave of Easter.)

I find the first very interesting as it explains a few feasts that I’d noticed but not understood such as the Feast of the Ordination of Gregory the Great on September 3rd.  (As ordination dates for popes aren’t typically feted.) Gregory’s usual Sarum feast day is March 12th. Thus, it’s one of the days that will always fall within Lent (March 10th-21st). These unusual extras allow for a full celebration of these Lenten saints who might otherwise get suppressed altogether.

The second confirms that the English 1662 BCP’s Rule 1 on transferring bumped feasts to Tuesdays and Thursdays does seem to be a continuation of medieval practice.