We will be driving from Utah on Sunday, Oct 11th. I have been advised by many people to avoid driving into Cal from LV on Sunday nights because of all the cars going home on Sunday nights. 
My original plan was to stay with family in St. George Utah and get up early on Monday morning and drive the rest of the way in
then hit the park. Now I want to be at the park at opening on the 12th. When I planned the trip I didn't realize it was Columbus Day weekend ( it is DH's birthday that day so I was thinking about the "get in free" bonus instead) but now with the holiday and extended hours I want to be there at opening, take a nap in the afternoon, then go back later.
So the question is: With Monday being a holiday, what should I expect for traffic if we do drive in on Sunday night instead of Monday morning? What should I expect for traffic if we try to arrive around 7am Monday morning instead?
Also, what should I expect for lines to pick up our tickets on Monday morning? I was planning on buying them from Getaway Today Travel then we just pick up our park hoppers when we get there. What time would the ticket windows and security open on a day the park opens at 8am?
Thanks in advance for the advice.

My original plan was to stay with family in St. George Utah and get up early on Monday morning and drive the rest of the way in

So the question is: With Monday being a holiday, what should I expect for traffic if we do drive in on Sunday night instead of Monday morning? What should I expect for traffic if we try to arrive around 7am Monday morning instead?

Also, what should I expect for lines to pick up our tickets on Monday morning? I was planning on buying them from Getaway Today Travel then we just pick up our park hoppers when we get there. What time would the ticket windows and security open on a day the park opens at 8am?
Thanks in advance for the advice.
