I just switched mine from Delta to SW. I go back and forth.
This year, they said that I should wait 48 hours for the change to take effect. But I asked if it showed Southwest when I log in before 48 hours, can I use it, and they said yes.
In prior years it was immediate. Anyone have it show Southwest after a change but it not work because it wasn't 48 hours?
I think fares will be higher for where I'm booking in 48 hours.