I think the answer is no, but I thought I'd ask.

I'm looking at finding which routes typically are not full in F for domestic flights. Reason being I'd like to "stalk" routes that are upgrade friendly so that when decent fares come along or my calendar pemits, I can take a mileage run with perhaps an above avg chance of an upgrade clearing. I know airlines typically dont publish load data, and I use UDUstats.com, but was wondering if I was missing other sources of data.
Thanks!