On Sunday, November 28, 2021 not only did Advent start, but so did a new liturgical year. The liturgical year runs from the first Sunday in Advent through the week of the Solemnity of Christ the King. The reading proclaimed at mass on Sundays and weekdays are based on the liturgical year. The Sunday mass readings are on a three year rotating cycle designated A, B, and C while the weekday readings are on a two year cycle designated I and II.
This year the Sunday cycle is C, meaning gospel readings will primarily be from the Gospel according to Luke. Cycle A features Matthew and B is a focus on Mark. Christmas readings are based on the time of the mass and Lent/Easter readings focus on John. Because Mark’s gospel in the shortest of the four canonical gospels, cycle B features many other readings from John.
Starting the week after the first Sunday in Advent and through most of 2022, weekday readings will be taken from cycle II.