JBFrequentFly

I haven't posted enough to upload an image of the voucher. Here is the fine print pasted below: bolded the section about Blue basic. Nothing states about upgrading on tickets purchased with points.

Move to Mint

Book in back, then move to Mint—our refreshing take on premium travel—at no extra charge, though additional taxes may apply. After you purchase a core seat on a Mint-eligible flight, head to jetblue.com/manage-trips to upgrade your flight to Mint.
Move to Mint certificates are valid to use for travel by their expiration date. Additional applicable taxes may apply at checkout. Certificate(s) can only be used to move from a core seat to a Mint seat on routes where Mint seats are available. Move to Mint certificate holder must be traveling in order to use certificate(s). Move to Mint certificates cannot be redeemed in connection with certain bookings including, but not limited to, Blue Basic fares, group bookings, JetBlue Vacations packages, bookings made with a corporate or government discount, bookings made with other airlines even if they include a JetBlue segment and bookings with pets. Certificates cannot be used for moves directly into Mint Studio® seats, even if only such Mint seats are available. Customers who have used Move to Mint certificate(s) who no-show for the flight without canceling the booking before the time of departure will forfeit the certificate(s) and applicable taxes, except where prohibited by law. Certificates and applicable additional taxes will be recredited to customers who have used Move to Mint certificate(s) if the flight is canceled or operated by substituted equipment on which Mint is not available.