Update 10/2/21: Brex is also losing JetBlue. Hat tip to Miles Talk
Capital One has announced that effective October 25, 2021 you’ll no longer be able to transfer points to JetBlue. JetBlue was added as a transfer partner in May 2019 at a 2:1 transfer rate. Capital One then improved the transfer rate to 2:1.5 in early 2020.
