I don’t know the load and you actually have to ask them but a Star G normally would not get a UG to business unless they don’t have any of their own G in PE which seems to be extremely rare as I see a lot of them boarding in Zone 1 and not in business. The bid would be your best bet.

I have an upcoming flight and I have been emailed twice asking if I want to make a bid. The strange thing is that according to EVA's booking site, the flight is actually sold out (Taiwan holiday). Are these emails just automatically sent for every flight, or is it possible that the flight is overbooked and they are trying to move some passengers into Business Class?

If they're sold out and there happens to be a no show in business, it'll be better to upgrade someone who "bid" than to give complementary op-up. They probably sent "bid offer" to everyone sitting in economy as well.

On the flip coin, if nobody takes it at $300, they'll probably lower the "minimum bid"

All strategies for revenue management

Just another data point..Mar 1 flight,YYZ-TPE-MNL in premium economy.

i put a bid for both me (G) and wife (Lowest tier) to upgrade to BIz on the TPE-MNL segment. Used lowest bid of 191 I think each. Bid got rejected 2 days before flight.

Upon check in at YYZ, we were told we are upgraded to Biz for TPE-MNL. Just weird they refused the money but then we get I’m assuming an OP-Up although the plane didn’t look full.