Re. TMZs, according to a man from NATS who addressed a meeting I was at recently, since the TMZ around Luton/Stansted was introduced, of all the requests for transits without a transponder that have been made, only two have been denied - and both of those were denied due to misunderstandings that were later cleared up.
That's what he said. I have no personal experience of it, I don't fly in that area and my aircraft all have a transponder.
FFF
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