There's construction on sections of I-15. In October you might miss the detour, but you will definitely hit a section with one lane of traffic in each direction. Now you might be lucky, but then again you might end up following a motor home for 18 miles
Also driving out of Vegas a good midway place to stop is Barstow. We stop a little south at the huge Barstow Factory Merchants Outlet Center (you'll see if from the interstate) the outlet has over 100 name brand outlet stores and nearby are gas stations and restaurants. I always stop in the In-N-Out Burger, a little something for the road.

Unfortunately the "ABC Primetime Preview Weekend" was Sept 6 & 7, and YES, Jennifer Garner was there, maybe next year.

Keep'em flying