The feast of the Annunciation of the BVM is a Double feast of the First Class and its liturgical colour is white. This year the feast is transferred to today as March 25th was Good Friday.
At first Vespers yesterday the antiphons Missus est Gabriel Angelus ad Mariam etc with an added Alleluia were sung with the psalms from the Common of the BVM (Pss.109, 112, 121, 126 & 147). The chapter was proper to the feast and the Office hymn was Ave Maris stella. The antiphon on the Magnificat and collect, were again, proper to the feast. After the collect of the feast a commemoration of Low Sunday was sung. At Compline Te lucis was sung with the Doxology in honour of the Incarnation, Jesu tibi sit gloria etc.
At Mattins the invitatory is Ave Maria gratia plena Dominus tecum. The hymn, antiphons (with added Alleluia) and psalms (with the exception of the ninth antiphon, Angelus Domini etc) are from the Common. In the first nocturn the lessons are from the Prophet Isaiah. The responsories are proper to the feast and are paricularly beautiful. In the second nocturn the lessons are taken from the second sermon on the Nativity by St. Leo. In the third nocturn the ninth antiphon is Angelus Domini nuntiavit Mariae etc and the lessons are from a homily by St. Ambrose's second book on St. Luke' Gospel. The Te Deum is sung. At Lauds the antiphons are those that were sung yesterday at Vespers sung with the Dominical psalms. Again the chapter and antiphon on the Benedictus are proper, the Office hymn, O gloriosa Virginum, is from the Common. After the collect of the feast a commemoration is sung of St. Isidore.
At Prime Jam lucis is sung with the Doxology of the Incarnation. In the short responsory the verse Qui natus es is sung and the short lesson is proper to the feast, Egredietur virga de radice Jesse etc. The antiphons of Lauds are sung in the usual order for the Little Hours. At all the Little Hours the hymns are sung to the melody and Doxology of the Incarnation.
Mass is sung after Terce. At Mass the Gloria is sung, the Gospel pericope is from St. Luke and the account of the Angel Gabriel's visit to the Virgin. (In said Masses there is a second collect of St. Isidore). The the Creed is sung. During the Creed the ministers kneel whilst Et incarnatus est is sung. The preface is of the BVM, with the clause Et te in Annuntiatione.
At Vespers the antiphons and psalms are, again, those that were sung as at first Vespers and Lauds. The antiphon on the Magnificat is proper. After the collect of the feast a commemoration is sung of the following Office of St. Vincent Ferrer. At Compline the Dominical psalms are sung and Te lucis is sung to the tone and Doxology of the Incarnation.
In the 'liturgical books of 1962' the hymns of the Little Hours do not have the Doxology of the Incarnation. There are no commemorations at Lauds, any Masses and Vespers.