SDC, Change or Cancel?
 

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

I think you were extremely lucky to get full refund on JFK-ROC. I'd say no change for changing JFK-BUF to JFK-ROC - it's a different route (not co-terminal), different day, against all rules for SDC. So I think you'd have to do a regular change, and in that case fare difference applies. 1.5 hr is really less than that, since JetBlue's bag drop cutoff is at 40 minutes before departure.
TATLs sometimes get in early, but can also get in late easily. You just need a tiny bit of bad winds and you're 30 minutes late :)

I would not make this change in advance. If by some chance you do arrive early, CBP is a breeze, you have not missedd B6's bag drop and are certain that you can make it to the B6 gate, then it is worth asking whether B6 will do it for you. If there is space, an agent is willing, and you are ready to go, you may have some luck. Airport agents will sometimes do things which phone agents won't do.

I would absolutely avoid using jargon. This change is not SDC, it is simply a ticket change in which the agent would reissue and collect the fee plus fare difference but, in this case, waive the add/collect. So, simply ask if the agent can get you on the 23:00 flight.

So you want to get burned twice by flight times switching? Norwegian swaps those flight times around quite often in my experience and you're likely to get put out again.

I'd keep the next morning flight personally. That's a VERY close transit time at JFK (T1->T5 with all the walking from the train) and I'd err on the side of caution.

Thanks! What’s a CBP and B6? I’m fairly new to this, so pls bear with me 😂

Definitely not not going to change (again). Booked the am flight to have a decent buffer. Just curious if it would let me on an earlier flight l, if we by any chance got in early in time for it.

CBP = Customs/ Border Patrol.
B6 is the two letter designation for JetBlue.

Your best bet in that case is to get to the gate, put on a big smile, and ask nicely.