JetBlue offers 3X points for starting at their site and clicking through to make purchases at Amazon.com. That still works for most purchases, but apparently will no longer work for buying Amazon.com gift cards.
As reported by Doctor of Credit, JetBlue has added Amazon Gift Cards as a new exclusion to their list of exclusions:
I’ve added notes about this change to my Extreme Stacking Amazon.com post and will publish a revised version soon.
For the record, Doctor of Credit predicted this change in February, but they thought the double-dip would die on March 1. We got a one month reprieve. Doctor of Credit wrote:
Starting March 1st, Amazon are making some changes to their affiliate program (and before you start blaming FM for this change, this has been in the pipeline for months). The changes will most likely hurt most people that use Amazon affiliate links (lower payouts in most categories), but the biggest change that might affect you is the fact that they will no longer be paying out on Amazon.com gift card purchases.