Another part of the Advent season is the reality that God has promised Christ will come again. So in addition to getting ready to celebrate Christ's first coming, Advent is about getting ready to acknowledge and celebrate Christ's second coming.
Some people really fear the turn of the calendar.
But their predictions are full of false assumptions, invalid interpretations, and a few incorrect facts. In truth, our calendars are wrong. In the middle ages when a monk working for Pope Gregory created the present day calendar, he made a mistake. He put Jesus' birth at the wrong time. We've been there for several years.