I cannot envisage such a situation, in my view it would bring down the Government, so what are Porsche doing this for??
Can we imagine MMC doing this??
Pretty blatant 'greenwashing' by Porsche. 4 years is far too short a time horizon, Euro6 cars will inevitably get banned in low emission zones, but it wouldn't be until the government after next so Porsche are in very little danger of having to honour this pledge - and eve if they do, as Nick says, the "up to" clause is doing a lot of heavy lifting here.
Of course manufacturers should be taking cars in and upgrading them to reduce emissions and improve efficiency, they've been capable of doing it for decades but have never bothered because it's more profitable to design in obsolescence and sell new stuff.
