Read the 10K and listen to the analyst calls. There are no 330's coming. The fleet size needs to increase in order to sustain the wide body aircraft in addition to the route structure.
The 330 is an expiring airframe as well. It makes zero financial sense to take delivery of an aircraft at the end of its life span.
Currently distant cities are more important to Jetblue than wide body service. If this can be accomplished with a narrow body 321 NEO LR management is inclined to do so despite the benefits to a wide body for cargo.