You can see how the first Sunday of Advent moves a bit depending on the day Christmas lands. In 2016 Advent begins on November 27th, this is the earliest Advent can begin. Then 2017, Advent won't start until December 3rd, the last date possible. 
Stay on your toes, Advent can sneak up on you!

Advent: A Journey of Waiting, Watching and Preparing for the Light
Go to Storenvy to buy the book! 
Or The Youth Cartel, even order a copy at Amazon

If you are looking to buy multiple copies for your church, youth group or small group shoot me an email; erik@erikwillits.com
You can also purchase in bulk from the publisher - The Youth Cartel :: http://theyouthcartel.com/product/advent/

Here are a random few of the countdown slides we made. Enjoy!