It's a service that doesn't exist outside of a very few main feasts like Holy Saturday, Pascha, Nativity etc...
What you today is a made-up, technically non-existent service. It mainly exists within the Antiochian Archdiocese due to its usage during Metropolitan Philip's era.
However, the proper way of doing the services is to retain proper order and liturgical time.
Vespers is always for the next day, as the liturgical day always begins with Vespers. This is why the 9th Hour always committed the current solar day's Saints and Vespers commemorates those of the following solar day.
The proper order of services should have Vespers in the evening, with Orthros and Liturgy in the morning.
The only exception would be major feasts, both of the church and Patronal, in these circumstances, the only ther service the Typikon allows for is a vigil service.
In a vigil service, you retain the proper order of the services and celebrate them in their entirety.
Therefore you serve 9th Hour, then Great Vespers with Litya and Artoklasia, then Orthros, then the 1st through 6th Hours, finally concluding with Liturgy. All served one right after the other.
Today many parishes cut down the Vigil from the monastic model, to one where they simply serve Great Vespers, Orthros and Divine Liturgy all in a row. This is always done the evening before the feast.
Under Metropolitan Philip and in other churches (like the OCA), Vesperal Liturgies are done, which are a Liturgical anomaly, and violate Liturgical structure, rubrics and order. They should not be done, but that is where we are right now.