If "signed contract" is your requirement then we can agree that no politician has ever lied in their campaign promises, because they don't make them signed contracts... that seems irrelevant?

The lie was that we save that much by leaving the EU, the fact that our health service was underfunded and has had budget increases in line with inflation and population growth doesn't change that it was a lie - we could've (and would have) increased NHS spending regardless of the Brexit vote.

The big red bus was a lie in a crucial way: the £350M per week they were talking about (from our contributions to the EU) could not have been funded the way the bus slogan claimed.

Because the net contribution to the EU was (significantly!) less than £350M.

It wasn't a suggestion to spend more money on the NHS. It was a suggestion to spend the money they claimed we gave the EU every week.

So it was actually a lie on a bus.

The figure was closer to £250M (after the rebate), but when they were given the amicable opportunity to restate the original claim around the correct figure, they doubled down on the £350M lie.