The Feast of the Annunciation is normally on March 25, but, of course, this year that occurred during Triduum, which takes precedence. So it was shifted to the next open day after, which, because Easter Monday is treated as an extension of Easter Sunday, is today.
While Annunciation is important, the structure of the Maronite calendar tends to de-emphasize it somewhat; the primary commemoration of the Annunciation is in Advent, feasts that don't fall on Sunday tend to be de-emphasized in general, and the existence of this feast of the Annunciation is primarily a testimony to a combination of the great age of the feast and the tendency of Maronites to recognize Latin holidays as well as their own. However, these are both powerful influences, and while March 25 tends for Maronites to be in practice the secondary celebration of the Annunciation, they certainly do celebrate it and treat it as important.
The Feast of the Announcement to Mary
Galatians 3:15-22; Luke 1:26-38
The Angel went to Nazareth, Alleluia:
"Peace, O Mary, maiden given great grace,
blessed are you among women, greatly favored!
Have no fear! Your God is gracious to you,
and you shall conceive a Son whose name is Jesus."
Mary was with wonder filled: "I am but a girl,
a maiden; how can I bear a son?"
"Mary, the Holy Spirit overshadows you,
with divine might is descending on you,
You shall bear God's Son. With God all is possible."
Then did the holy Virgin say, "Let it be so,
for I am the handmaiden of the Lord!"
O Mary, receiving peace from God, you give peace;
you restored Eve's children to their true place;
in you the Word was made flesh to dwell among us.
O Lord, we do not understand and are amazed;
we are blinded by Your eternal flame.
The incense of our prayer alone can we give;
we hide behind its smoke in Your presence,
for great is the might that comes upon Your altar!