30 mile Utah canyon loop?

Youngs – Lean To loop in Dark Canyon. But start from the Sundance Trail, since driving out on North Long Point could be seasonally too late.

Any of the loops in Steve Allen’s three guidebooks would serve you well. He writes excellent guidebooks which include info about class 3-4 obstacles.

Canyoneering 2 – Technical Loop Hikes in Southern Utah. He suggests that four of the seven routes in the book are viable up until Dec 1. We’ve hiked variants of four of the routes in this book and in our opinion they are five-star routes. Each route is roughly a week long, but you could trim them down to fit your timeframe.

Yup.  It’s NNW of Arch and Texas Canyons and SE of Dark Canyon.