If you fly "jump-seat" you are entitled to business class if open, however your wife on a zed fair is only entitled to the main cabin. I found this out the hard way out of BKK-NRT-SFO. The customer service supervisor said only I was entitled and my wife would not be upgraded due to "Star Alliance" protocol. When I approached the purser about this, I was told absolutely not, that customer service is in charge and they already told him that she was not to be upgraded, even though there were open seats. So, we traded seats half way through so we could both sleep. The crew was ok with this, so long as one of us sat in the back.?
I thought it was odd that the flight crew has no say as to what goes on in their cabin once the doors are closed.