I have explained the transferal of days of obligation in the past - the exact wording in the Ordo notes issued in the Province of Wales yearbook reads thus:
The Holydays of Obligation for England and Wales are: every Sunday, Christmas Day, St Peter & St Paul (29 June), the Assumption of the Blessed Virgin Mary (15 August), and All Saints (1 November). With the exception of Christmas Day, any Holyday of Obligation falling on either a Saturday or a Monday is transferred to the Sunday. Since Advent 2006, three Solemnities have been permanently transferred to Sundays, namely: the Epiphany of the Lord, the Ascension of the Lord, and the Body and Blood of the Lord (Corpus Christi).
Where Mass is celebrated in the Extraordinary Form according to the provisions of Summorum Pontificum, a different calendar applies ....
.... The Bishops' Conference of England and Wales submitted a dubium 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, on the date prescribed for the Ordinary Form. Where the obligation has been removed and the Holyday transferred to the Sunday, this is to be followed in both Ordinary and Extraordinary celebrations of Mass.
A further dubium submitted by the Latin Mass Society (N107/97 20 October 2008) clarified that where the Extraordinary Form is being followed, it is proper to also celebrate the Mass and Divine Office of these solemnities on the traditional dates indicated in the 1962 calendar, though there would be no obligation on the faithful to attend Mass on such days.
All that said, sadly we don't have any Masses in the Old Rite in Wrexham Diocese for this most beautiful feast!
However, locally and within reasonable traveling distance you may wish to avail yourself of one the following celebrations:
Diocese of Shrewsbury
Low Mass at 10am
Ss Peter & Paul and St Philomena,
Atherton Street, NEW BRIGHTON, Wallasey CH45 9LT
Diocese of Salford
Low Mass at 10am
Alexandra Road South, Whalley Range, MANCHESTER, M16 8QT
Archdiocese of Liverpool
Sung Mass at Noon
St Catherine Labouré,
Stanifield Lane, Farington, LEYLAND, PR25 4QG
Low Mass at 9.10am
Bolton Road, ANDERTON PR6 9NA
Low Mass at 9.00am
Corporation Street, ST HELENS WA10 1EF