One more thing to add. Some airlines are increasingly introducing fees for "revalidating" tickets at airports if they are not issued on their own ticket stock. It seems to me that you a far more likely to require a coupon for a different date revalidating than you are one that is open. However, it is important when in this type of discussion to try to hold your ground. The basic principles of airline ticketing and endorsement are:

- as a starting position, an unendorsed ticket is valid on any flight on any airline on any date within the validity of the ticket (normally 1 year from issue) for which a confirmed reservation is held in the booking class on the ticket by the passenger named on the ticket

- endorsements on the ticket can restrict the validity further, but, in principle, if there is no endorsement on the ticket that prevents you using it then it is valid. The onus is on the airline to show why it is not valid if they are claiming so. Again this is MUCH easier if you are both looking at the same piece of people rather than having an airline employee interpret what they can see on their computer screen.

On OW Explorers normally the only endorsements are:

- "Valid on OneWorld airlines only" (or the equivalent listing all the airlines individually)
- A "Not valid before" date on the last international coupon (and any subsequent coupons) of 10 days after the date of the first coupon. (Except in the cases without restriction, eg origin HKG)

And that's all. There are no valid grounds for charging you for "revalidation" of a OWE ticket because it is open-dated or was associated with a reservation on a different date when printed. Putting a specific flight on a ticket coupon of a OWE does not change its validity.

Just thought I'd get that off my chest!

(By the way, now that we have an official OneWorld representative here I would of course welcome any comments or corrections from them if I have somehow misunderstood.)