Originally Posted by Dave Noble
Which ticket types do allow changes to earlier flights?
There are two factors that come into it; fare rules and availability of your fare type on earlier flights.
Some fare types (eg N, not sure of others) cannot be changed on the day of departure, so QuickCheck is not going to them under any circumstances.
Some fares permit changes if you pay a fee (eg $33). I don't know if QuickCheck will allow these and bill you somehow.
And of course the flight you want to change onto must have seats available at the fare type you have purchased, otherwise you have to upgrade the fare to one with seats available. Again, I am not sure if QuickCheck will permit this and find a way to bill you.
My domestic check-ins with QuickCheck have all been on Y or B fares and have been offered different flights based on the fully flexible fare and seat availability.