In the meantime, still no indication of how the proposed runway is to be shoehorned in between the existing 09R/27L and the reservoirs.
And the answer of course (it now appears) is that it won't be.
Instead, we appear to have Heathrow's own version of Schiphol's Polderbaan, to be built over the filled-in northern half of the KG VI reservoir, J13 of the M25 and the Staines-Windsor railway line.