Long story short......
I had a couple of cruises booked and paid for before the pandemic caused MSC to cancel both cruises. I took the option of FCC which was 125% of the cruise fare. The taxes and deposit were refunded to the original form of payment.
I decided to use the larger FCC on a 2022 cruise on Seashore. With prices going up and down, I jumped on a low price and put down a deposit. After my cruise became eligible for the 5% + 15% discount, the total due was less than the amount of FCC. Since the entire FCC can only be applied to 1 cruise and I didn't want a larger/more expensive stateroom, I had a negative balance (they owed me) after making final payment when I applied the FCC.
Some people in a similar situation were told that the overpayment would be returned after the cruise.
Some people in a similar situation were told that the overpayment would be converted to OBC.
Some people in a similar situation were told that the overpayment would just disappear and would never be seen again.
In my case, the overpayment amount was deposited to my bank account on the 2nd day of the cruise. My cruise on Seashore (2022) was less "out of pocket" than I would have paid for the cancelled cruise on Seaside (2020) even though the staterooms were practically identical (exact same itinerary).
Many complain when MSC gets things wrong so it's only fair to post when MSC gets things right. ☺️