Sounds to me like a break down (brake down

) in communication from Bassets . But I think they are following Honda policy.
My understanding is as Steve_M says. Due to a shortage of parts and the time needed to make more , there is a waiting list of cars based on their date of manufacturer .As parts become available cars move to the top of the list and get invited for the replacement , whether or not there are codes etc. BUT if before this your simulator definitely becomes faulty, with error codes etc you jump to queue for rapid replacement ,ahead of cars not yet showing any symptoms.
If the car just happens to be in the workshop for a service/mot etc the dealership may well offer concerned customers some reassurance by checking for any codes or other signs of immanent simulator failure . But if they find nothing wrong its not, IMO ,fair that the car should still jump the queue ahead of others that are still waiting for their recall.
Unless I am completely wrong I think Honda still intend replacing the simulator on all cars potentially affected, fault codes or not. Eventually.
The delays may be frustrating and unacceptable but I suspect the staff member at Barrets did not fully understand the reason why the car didnt yet qualify for the replacement and didnt explain it well.