I just booked a RT flight on Philippines Air for March : MNL-BKK

I paid $213 for an economy ticket. Business would have cost me $833.

PAL lets economy ticket holders bid on an upgrade to business class. Has anyone had any experience with an upgrade bid? I'm going to give it a shot, just don't know what a fair bid would be. Tried doing a forum search but didn't find anything.

Thanks!