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Yes, the Sunday celebration takes precedence over the (otherwise obligatory) Memorial of St Augustine.
A table listing the precedence of celebrations may be found here
Table of Liturgical Days (NB that Sundays in Ordinary Time (item 6, section II) dominates obligatory memorials in the General Calendar (item 10, section III))
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During the two liturgical seasons of Ordinary Time, if a Solemnity or a Holy Day of Obligation falls on a Sunday, it will still be observed. The Solemnities that can be observed if they fall on a Sunday are: St. Mary; the Mother of God, Epiphany (which is usually transferred to a Sunday anyways in the USA.), the Nativity of St. John the Baptist, Sts. Peter and Paul, The Assumption, All Saints’ Day, All Soul’s Day, and Christmas.
Some Solemnities are moved to Sundays by the Bishops in the USA: The Ascension of the Lord (in the Western part of the USA) and Corpus Christi, both in which are traditionally observed on Thursdays and are Holy Days of Obligation.
Durring Advent and Lent the Solemnities of: St. Joseph; husband the the Blessed Virgin Mary, the Annunciation of the Lord, and The Immaculate Conception will either be observed on the Saturday preceding their date, or the Monday right after their date (if the date falls on a Sunday.) If St. Joesph; husband of the Blessed Virgin Mary, or the Annunciation of the Lord fall durring Holy Week or Easter Week, it will be observed on the first Monday after Divine Mercy Sunday.
Some Feasts will also be still observed if they fall on a Sunday: The Presentation of the Lord, The Transfiguration of the Lord, The Triumph of the Holy Cross, and the Dedication of the Basilica of St. John Laternan.