I tried to book a flight over a holiday for two members of my travel pool using a combination of points, travel bank credits, and a jetblue credit card. I'm a mosaic 2.
PLEASE DON'T DO THIS!
1) The website was criminally slow. I had to edit my wife's contact info every single time. It took minutes to click through the whole thing.
2) I tried to pay using points, but it said that my travel bank credits couldn't be applied. No explanation for WHY.
3) I called customer service, and they helpfully told me that you can only use two forms of payment. So if you have a $50 travel bank credit, and the taxes are $100 on the flight, you are SOL. I didn't want to pay $25 per ticket to have her book two flights to take advantage of a $50 travel bank credit that I was told was 'just like cash'.
4) So I broke the trip in half -- this was suggested on the website!. In one leg I paid cash + travel bank, and on the return trip I paid cash plus points. Again, I had to click through a billion slow screens trying to upsell me on products I didn't want,and in some cases couldn't use (like a hotel in my home city)
5) To avoid having issues with the seats getting taken, I attempted to check out at the same time from two tabs on my browser. The first flight went through, but I promptly got a fraud alert from the Jet Blue credit card complaining about the purchase that they suggested on the jet blue site.
So now I had to go validate myself and check out again.
TL

R small travel bank credits are nearly useless. Don't settle for them! Jetblue website is way worse than DL or UA and much slower/quirkier. A better booking system would attract a lot more corporate / high end travelers.
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