I arrived at the check in counter for my DEN-LAX-KOA flight this morning and was denied check in. While I know I was cutting it close, I got to the counter about 35-40 minutes before the flight. According to UA's website, that shouldn't be a problem.
The CSR told me that I needed to be there with my luggage 1.5 hrs before the flight. When I advised her about UA's website and that I could still make the flight, she told me I was wrong.

She rebooked me through SFO, in Y (I had confirmed upgrades with a CR1), but it looks like F is 0.

I'm just curious about this... shouldn't she have let me check in? I know I was cutting it close, but I was within the appropriate time frames according to the site.