The same-day flight change option will be available within 24 hours before your original scheduled flight. Inside of this timeframe, you can try to take an alternate flight so long as it departs no more than 12 hours from when you are making the request.

So if I understand this correctly: If I have a flight tomorrow at 8AM and want to go today at noon, I can by just paying 25 bucks?

This is a brand new fee in the industry and totally changes the rules. I'm sure others will follow...

I just wish they would exempt Plats.