I fly IAH-BON once or twice a year and have had this exact same problem. I have called CO about it several times and have several "case numbers" that have never been resolved. Everytime we fly this most of the seats on the flight from BON-IAH are empty up front with companion upgrades and other elite upgrades not processed in advance sitting in the back.

What I've been told is that the KLM agents (who work the CO flight) do not have authorization to change the reservation. I know this is not true as the very first time I flew to BON, I was able to get the companion upgrade, just not for the last 3 or 4 times.

The last time I was there in the fall, the supervisor said that if CO can process the upgrade in advance, they could print out the new boarding pass, but as we all know CO reservations cannot process this in advance.

I'm going to BON in 4 weeks and will try in vain again. I had a friendly reservations agent put a note in the record (which she wasn't supposed to do) to please process a space available companion upgrade. I don't think it will work though.

The last time I called 1800 wecare number they said that there was nothing that they could do. Personally I think that is evading the issue rather than training the agents how to process the upgrades.

Sail a Nacra