Following a request for information, the Catholic Bishops’ Conference of England and Wales submitted a
dubium (a query) to the Pontifical Commission
Ecclesia Dei which confirmed that in the Roman Rite, whichever Form of the liturgy is being celebrated, the Holydays of Obligation are held in common. Where the obligation has been removed and the Holyday transferred to the Sunday, the Epiphany of the Lord, the Ascension of the Lord and Corpus Christ, this is to be followed in both Ordinary and Extraordinary celebrations of Mass.
A page with this information together with further details about the Calendar for celebrations using the Extraordinary Form has been added to the Liturgy Office website: