Re: For those familiar with large projects - BREXIT roulette
"Of course, the EU may extend, the UK may extend, ..."
If it suits the political classes on both sides, then both sides may extend pretty much indefinitely. The current position is that we appear to have lost our voting rights, but as long as we stick to the rules we are continuing to enjoy the benefits. It is not inconceivable that both sides might reckon that situation is actually better than anything they have so far managed to negotiate. Actual brexit might never happen.