We are currently in the same situation. First, we called the TA to tell them what was going on last weekend (person started showing symptoms, took 2 home tests, and immediately isolated). We placed a hold on a cruise in October as a contingency plan.
Tuesday, 2 days before our cruise, we all got PCR'd and our suspicion was confirmed: suspected case turned confirmed. We immediately called our TA, told them the update, canceled our Thursday cruise, and booked the October cruise.
Our next step is to get the person recovered and get a COR from RC. RC has been informed, via our TA, and we're getting a refund. Our reservation has been moved to the October cruise.
We are all vaccinated and boosted except for 1 9 year old. If more boosters are available by the time we go, we'll take them. In the meantime, if anyone does so much as sneeze near me, I will run so fast in the opposite direction...I do NOT want to miss the October cruise!