I don't think anyone has commented on the Peter Dykes...

I don't think anyone has commented on the Peter Dykes transactions, as there is insufficient information to know at all what they were - what was the original CFD arrangement under which they were held?

Perhaps he had the shares on margin loan and was forced to pay off the loan due to the falling share price? Or perhaps they were loaned out for shorting via the CFD provider and then returned (though I'm not clear on the extent to which CFD providers back trades with matching real transactions). I'm sure there are plenty more interpretations or combinations.