Billboard design in Illustrator CC 2019

Hi Everyone.

I need to design a billboard, however, Illustrator CC won't allow me to work in a 1:1 size. I need to understand what size to make this billboard so they (Billboard Co.) can use it and I don't look like an idiot.

The information I've been given:

LIVE SIZE: 10’ high by 24’ wide
FINISHED SIZE: 10’ high by 25’ wide (I think this should be 11' x 25')
BLEED: Six-inches
POCKETS: Three-and-one-half inches (pockets within bleed size; pockets on all four sides)

Thank you for any help you can give.

KG