Undated ? Well, more like unyeared.
It's kind of the best of both worlds. You can start using this planner any time you want... but uts still filled to the brim with everything you need.
The dates are all in here (all 366*). Just write in the year and the day of the week and you're good to go. Bonus, it's packed full of random holidays, trivia and humour. Just open it and look for yourself.
Just flip to today's date and get started. Once you reach the end of the year Just start back at january 1st and finish out the book. Unlike life, no day goes to waste.
*you know leap day.