Don’t assume it’s locked in: better flights can appear at any time.
We already had our flights booked and were comfortable waiting for the trip, but I kept checking for better options. Around midnight last night, I looked again for two seats from Baton Rouge to San Diego for the return instead of MSY. Out of nowhere, two First Class seats opened up, Alaska Airlines on American Airlines metal, and I booked them immediately. The new flight was half the cost of our original Southwest Airlines booking, got us closer to where we wanted to be, and put us in First Class. Not a huge deal, but definitely nicer than the “extra room” seat on Southwest. Just two hours earlier, nothing was available. I decided to do one last sweep of all our flights for this weekend and next week, and it paid off. Since cancellations are so easy, we canceled and saved about 50% in both directions, and the credit will be easy to use. Fortunately I have been able to do this 4 times in the last month. Until I fly, I will keep on looking. Thanks to JGOOT. I used to shop hard to book the initial ticket, but almost never went back to look for better routes or pricing. It was always “book it and forget it.”