Anything from a half hour to an hour and a half. Depends on the celebrant, length of homily, number of people attending, amount of music, etc. Best bet is to ask someone in the church office or someone who attended at your parish last year.
A normal early early morning mass here is about a 1/2 hour. Now give the extra coming for Ashes and about 10 minutes to distribute ashes…and it also depends how many stay for communion. In our parish many receive ashes and head out the door. I find it funny that they all want to recive a smudge of dirt but not our Lord.
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