We all know about CO's 24 hour flexible booking policy.

But I thought it was worth highlighting/alerting folks to some peculiarities.

When you are within the 24 hour period, you have three options for changing/canceling your flight:

1. Change the flights: the website gives you the option to change the outbound and/or return for any or all passengers on the rez. The new flight options show the additional fare required, if any (not sure what it shows if the fare is lower).
2. Cancel the flight, retain the credit for future use: Pretty straightforward, your reservation is cancelled. To rebook and use the credit, you go into "Inactive Itineraries" and can book a new flight from there, with the credit applied.
3. Cancel the flight, refund to original form of payment: self-explanatory.

It seems that in either case #1 or #2, you do not get another 24 hour grace period for subsequent changes. I recently made a change to a flight within the initial 24 hour period, and specifically didn't choose option #1 as I was afraid that I wouldn't be able to make further changes if I needed to the next day. I thought that Option #2 would allow this -- because if I re-booked, say a month later, it would make sense to get another 24 hours to change the ticket, as if it were a new reservation. Remember, I voluntarily selected to keep the credit instead of a refund, so it would seem unfair for CO to penalize my by taking away the 24 hour flex policy on the new reservation.

Now, I'd add that I never called CO to try and make a second change (within the 24 hour period after making the first change), so I can't be 100% sure that an agent or supervisor wouldn't waive the change fee, but continental.com definitely wanted to charge me the $150.

Moral of the story -- always select refund to original form of payment if you want to maximize the utility of the 24 hour flex policy.