Reference for Lorax 35-day calendar

My daughter is still in love with The Lorax (2012), although (luckily for me) we don't watch it as often as we used to. Today we had it on TV, when I realized there was a calendar Ted's room, and I thought it could help me identify the timeline of the movie (related question)... silly me, I thought it would help me, instead it left me even more puzzled:

Here's a detail of the calendar where you can see a month of October with 35 (or 34-and-a-half) days:

I thought it could be a homage to The Lorax or a different Dr. Seuss' work, but I didn't find any reference in the book about this long October; and searching online I only get information about two types of calendars that don't look related to this one: the 5-Week Leap Month Calendar and the Bonavian Calendar.

Is this 35-days month based on any of Dr. Seuss' stories? Or is it a cross reference to a different book/movie?