You need to check with you own Diocese.
While usually the ealiest is 4pm, in mine we have a Mass at a nursing home that starts at 3:15 on Saturday, and counts for Sunday obligation. Bishops can make those types of decisions for their dioceses.
Welcome home! A Saturday night mass counts for your obligation for Sunday. If it is a mass earlier than 4 pm than it does not count. You don’t need to go on Sunday if you go to a Saturday vigil.
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