My vote is for the 12th to 14th. It is likely that I will not attend this year with me selling & building a new house & all, but ya never know.
The reason for the later date is there is likely to be a few more leaves on the ground minimizing the motorcycles, but still plenty of color in the canopy to enjoy the scenery.
Also, I just checked the calendar at the TOD web site & the Smokey Mountain Bike Week is scheduled for the 4th thru the 7th. Carolina Honda leaf tour will happen the 20th, 21st. 12th thru 14th still open on the calendar as of this posting.