Prior to the revision of the liturgical calendar of the Order initiated in 1960, the feast of the Commemoration of Our Holy Father St. Dominic in Suriano would be celebrated today. The feast was always a totum duplex feast, equivalent to a Ist Class feast in the 1962 breviary classification system. However, in the older calendar, this feast would have taken precedence over today's Sunday office. The removal of this feast baffles me, as it is such a wonderful way to pay tribute to the patronage of St. Dominic, our Lady, and the two (2) "unofficial" patronesses of the Order, St. Mary Magdalene and St. Catherine of Alexandria.
The feast was traditionally celebrated on September 15, and the Feast of the Seven Dolors or Our Lady was celebrated on the 3rd Sunday of the month of September. However, I believe, when the feast of the Seven Dolors was fixed on September 15, this feast was transferred to September 25 until its suppression in 1961.