Sorry if this has been addressed already, tried the thread search and didn't see it but might have worded it differently...
I use the same-day-confirmed option often when trying to get on an earlier flight and i believe the website used to be able to handle this. Now it seems it only works if it's the first leg of the trip. If it's the return leg I have to call in. Seems like it would save Delta call center time if they could just get this simple feature to work.