How many saints were there before Jesus?
Starting from Abel, the first man to undergo death for his righteousness, there are many saints of the Old Testament whom the Church venerates. The Roman Martyrology, both the old one and the new one promulgated by St. John Paul II, have many days with a commemoration of the prophets and other worthies of the Old Testament. The ancestors of Our Lord, including Adam and Eve, are commemorated on December 24, but there are days for the major and minor prophets and some of the judges, and so on.
So, yes, there were numerous saints before Our Lord who awaited his coming. When he descended to the dead on Holy Saturday, he gave them the heavenly happiness and beatific vision they longed for. In a true sense, they entered heaven with Christ but not before him.