I'm trying to change the dates on an an award ticket (domestic, in case it matters), and when I go through the "change flights" option on co.com, I get only four choices of times for flights on the new dates, none of which are times I want. But if I try to book a new award ticket for those dates, I get about 15 choices, including the time I want.

Has anyone seen that before? Any ideas on how to get around it? I could just cancel the old award ticket and book a new one, but the new dates are less than 14 days out, so I'd pay the $35 ticketing fee, whereas the change would be free. And I could try calling, but then I'd pay a fee for booking over the phone, right?