Looking for advice how to go about this.
My spouse and I were flying
Norwegian OSL-JFK arriving at 8:20pm. We had a connecting flight
JetBlue JFK-ROC at 11pm (Blue plus fare).
Suddenly, Norwegian changed the departure time, meaning we would not get in to JFK until 11pm - meaning we would miss our JetBlue connection.
Decided to change our Norwegian OSL-JFK flight to the day after, arriving JFK at 21:30. Knowing 1 hr 30 mins would be a little tight; clearing customs, change terminals, re-check, TSA etc - we decided to change our flight JFK-ROC to early next day.
Unable to change or cancel online at JetBlue (kept getting error msg), I called in. Prepared to accept the $75 change-fee per person (150 total), I was pleasantly surprised when the agent told me she had cancelled our tickets and rewarded my JetBlue travel bank the
FULL AMOUNT of our tickets!

JFK-ROC was super expensive the next day, so I went ahead and booked a blue plus fare
JFK-BUF (only 1 hr away) at 5:45 the next morning for the same price, meaning I was able to change the tickets for free/no change fee.
Since I'd rather not spend the night at the airport, and sometimes transatlantic flights get in early; there is a flight
JFK-ROC at 11pm. But I didn't want to book this in case we run late out of OSL. How are my chances of
changing my 5:45am flight JFK-BUF to JFK-ROC 11pm the night before? Technically its not the same day, since the earlier flight would be before midnight.
Any experience on this? Do they sometimes put you on an earlier flight? I know they do on Southwest and some other LCCs here in Europe. Since they waived the change fee the first time, I would be willing to pay up this time. Just worried the fare-part would add on a lot...
Also, first and last time I am connecting on different airlines/itineraries.... lesson learned! Haha