Dear Delta Experts,

I need your help to better understand the following paragraphs from Delta.com -> Skymiles -> About Skymiles -> Rules -> Ticket Validity

Ticket Validity
Award Tickets are valid for one year from date of issue. Destinations governed by international tariffs: If portion of original ticket has been used, it is valid for one year from date travel commences at point of origin on original ticket. If no portion of original ticket has been used, ticket validity is one year from the date of issuance of the original ticket. Reissue does not extend ticket validity.

Per the highlighted sentence, am I right in saying if I have a ticket booked on 3/1/2009, and the original departure has been used on 12/1/2009, the ticket will be valid (implying I can change the return section following other award ticket rules) until 12/1/2010?

I have such a ticket, and I called before 3/1/2010 (one year from the issue date) at least 3 times and got confirmed that the validity stays until 12/1/2010 (one year from travel begins). However, today when I called to change the return date, I am told by 3 different representatives the ticket has expired on 3/1/2010 and nothing they can do about it! I directed them the above terms right on the delta.com at this moment, and they said it means I have to change/modify before 3/1/2010, although the ticket might be used by 12/1/2010. One of them even said she talked to a supervisor about it and was told ticket did expire! Am I so bad in English that the red colored "valid" in the above sentence means something different?

Not sure what I can do, if the ticket indeed expires, it will cost me a fortune to book a one-way international ticket... please help.

Thanks a lot in advance,