I had a discussion a few days ago with the GS manager at ORD about this.
I was (and still am) willing to buy an "A" fare for my upcoming ORD-LHR trip. All three flights are not selling F seats.
He told me I could use a GPU. Told him I don't want to use one.
He said if they do use a three-class 767, nobody will be comped an upgrade. So I asked if non-revs will get those seats.
He said most likely yes. Even though I was (and am) willing to buy F? Yes. If the buy-up is still around $800, I would gladly do it. But as you know, the buy-up can change and it could be in the thousands.
I made it very clear that if non-revs go into F and I am stuck in C, I would cancel my ticket at the gate and fly BA or another carrier with an F cabin.
Of course he didn't want to hear that, but he knows me well enough and knows that I would do that.
He said that he would call WHQ and discuss this with people who have decision-making powers with respect to this issue.
I await the answer.