I am flying ORD-CDG in a couple of weeks and I am not being allowed to complete an upgrade request on .bomb (Y to C). It says that I am eligible to upgrade the Y fare with miles (10,000) or a SWU. But when I try and apply miles to the upgrade it says that there has been an error. There was no problem applying for an upgrade on the return portion on the trip with miles. I show up as waitlisted.

While I acknowledge that the plane may be tight and that I may not get the upgrade, shouldn't I be allowed to be waitlisted? We are still quite a bit out of the approval windows for upgrades so I should be able to take my place in the queue.