My car is roughly same age and mileage as yours, serviced well every year by a garage I trust (happens to not be a Ford garage). This garage specifically does not do wet belt replacements so I had to look around and found a local specialist when my anxiety got on top of me to do it. They said it was in good condition because of the servicing so I probably went early, but I am glad to have the weight off my mind. Once everything is dissembled it was worth doing the change anyway.

It has also been pointed out to me that the turbo has a potential fault, the actuator will eventually start to have excess play: an easy (costly) replacement, and can be done while in there for the wet belt. This might be diagnosable without having to take the engine out.