Is there significance to the saturday between Good Friday and Easter Sunday?

Holy Saturday is the day before Easter in the Christian calendar. It is sometimes called Easter Eve, especially by Anglicans, or Low Saturday. Filipinos often call it Black Saturday or Sábado de Gloria, while in the Czech Republic and Slovakia it is called White Saturday, probably because of white garments of the newly baptized. In Dutch it is known as Silent Saturday (Stille Zaterdag). It is the seventh and last day of Holy Week, and part of the second day of the Easter Triduum. Holy Saturday is also often incorrectly called Easter Saturday, a term that properly refers to the following Saturday.

In Roman Catholic Churches, the sanctuary is stripped completely bare while the administration of the sacraments is severely limited. Holy Communion is given only as Viaticum. All Masses are strictly prohibited. No Mass at all appears in the liturgy for this day, nor for the preceding day, Good Friday. Many of the churches of the Anglican Communion observe most of the same traditions, however their altars are usually stripped or coloured in black. See Liturgical colours.

Liturgically speaking, Holy Saturday lasts until dusk, after which the Easter Vigil is celebrated, marking the official start of the Easter season. In Roman Catholic observance, during the “Gloria” of the Mass (which is the first Mass since that of Holy Thursday), the church statues and icons, in places where they are covered with purple veils during Passiontide, are dramatically unveiled.

In Eastern Orthodoxy this day, known as Holy and Great Saturday, is also called The Great Sabbath since it is on this day that Christ “rested” physically in the tomb. But it is also believed that it was on this day he performed in spirit the Harrowing of Hell and raised up to Paradise those held captive there. Therefore, at the main liturgical celebration, a vesperal Divine Liturgy of St. Basil the Great, the hangings, altar cloths, and vestments are changed from black to white prior to the Gospel reading, and in the Greek tradition the clergy strew laurel leaves and flower petals all over the church to symbolize the shattered gates and broken chains of hell.

Great Lent was originally the period of catechesis for new converts in order to prepare them for baptism and chrismation on Pascha (Easter). Prior to the composition of the current Paschal Vigil by St. John of Damascus this day’s vesperal Liturgy was the main Easter celebration, and the traditional time to receive converts is still after the Vesperal Liturgy.

Practically speaking, Roman Catholics, some Anglicans and Episcopalians, and some Orthodox believers will be attending the Easter Vigil instead of going to your event.

It’s also worth noting that the obligations of Easter generally include either Easter Vigil or a Sunday morning worship service, so unless you have people who are already committed to the Easter Vigil for some reason, they could choose to go to the Sunday morning service instead.

(I prefer the Vigil myself, because it means I can sleep in on Easter Sunday.)