I received a email on June 30 saying that a small number of vehicles would be rectified at the factory and mine was one. I should expect a call in the next 10 days to arrange collection and that the car would be with Morgan for 7-14 days to carry out the work.
This evening I have received an email from MMC as follows:

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We are sincerely sorry for the disruption that you have faced as a result of the stop drive recall affecting Morgan Plus Four and Plus Six vehicles. We are eager to communicate updates to affected customers as regularly as possible.
We have been validating a technical fix as thoroughly and swiftly as possible, and this process is nearing completion. Whilst we must await the final results of this process, along with the sourcing of components, we are pleased to say that early indications are leading to a high level of confidence in the fix.
Once this process is complete, we plan to begin shipping the required parts to the Morgan dealer network, allowing them to begin rectification works to affected cars.

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So, basically they haven’t yet finally decided on a fix, let alone sourced or shipped the parts.
This leads me to conclude that it is highly unlikely the car will be on the road again this summer.
Having bought the car in 2020 and having two years of Covid (no-ones fault) and now this, I am sure most would understand why I am beginning to regret this very large purchase.