Kylie Jenner's 20th birthday will be delayed by 10 days this year ... because her own calendar couldn't even get the date right.
The 2017 edition -- sold exclusively on her website -- lists her bday as August 20. Kylie was born on the 10th. On a positive note, there's lots of cake ... on Kylie.
The misprint isn't just a one-off fluke either. We're told it has appeared on multiple calendars since its release a couple weeks ago ... possibly all of them.
As we've reported ... Kylie, inc. was flooded with quality complaints last year, and this ain't a great start for 2017. At least the calendar got her dog's bday right.
Seems like a head or 2 might roll for this -- but Kylie's camp had no comment.