I’ve only sailed on Celebrity once and used FBC. As our trip was over a year away when booked, the airlines changed things multiple times on us. Biggest issue I had with FBC was they kept saying they would get to my change in 90 days initially, and on the last change they were telling me in 30 days, when my flight out was just 28 days away.
Needless to say, everything worked out in the end but Celebrity site never showed my flights correctly. I relied on the Airline page to know what I actually had booked.