Thank you for posting this. We are in a similar situation. We have a cruse booked for September (pushed out several times from 2020). I was planning to cancel this week since they announced the extension of the protocols.
I would also not cruse if they are going to make us do anything different than any other passengers. No markings or limitations because we are not vaxed.
I am also concerned about the ports, they could have rules that un vaxed would not be allowed to do certain things. We would be going to Grand Cayman and Jamaica.
I am still before the final payment date so I think I will be able to get a full refund and not have to deal with FCC's