Comment by rwmj

Unfortunately since then the managers got rid of all the volunteers who had intimate knowledge of the computer science: https://www.theregister.com/2014/01/28/bletchley_park_sacks_...

I was very lucky that I got to meet Tony Sale a couple of times before he passed away, back in probably 2008 or thereabouts and he demonstrated the Colossus that he had rebuilt to me, which was a tremendous experience (https://en.wikipedia.org/wiki/Tony_Sale).