doesn't appear that there are a whole lot of B6 people who participate in this forum..... also doesn't change that B6 has a substantial headstart in the Caribbean.
JetBlue flies TPA/FLL both to SJU two flights per day, so if WN decided to start this first there must have been some thoughts that in that market there was room for another carrier. WN is flying TPA SJU once a day and FL is flying FLL SJU twice a day..