I too am still stuck at the 9:59 PM arrival scan in Ontario. I'm in Northwestern Ohio and delivery is scheduled for today.
I'm 50 miles south of the main hub in Toledo (3rd busiest in the entire UPS network for crying out loud) and about 90 miles south of DTW airport in Romulus.
I'm giving it until 9 AM, I know (according to my buddy who works at the TOL hub) labels fall off the bulk sacks our phones are in left and right, and usually when packages are processed in TOL, they're so damn busy they just chuck 'em (not literally) into the vans and trucks and let the next POI (Findlay, in my case) deal with actually scanning it, updating the location, holding the package for will call, etc.
9 AM. 9:30 at the latest. If it still shows "Arrived - Ontario, CA" then I guess it isn't happening today.