Sorry I gave out a bit of incorrect information, according to the website you will be able to cross if you haven't paid in advance, but you only have until midnight the same day to pay, so the onus is on the driver, I agree with Theo that if you've got someone trying to catch a ferry or something else on your mind there's a good chance you may forget, let alone anyone who is completely unaware of the situation.
Another thought is what about vehicles on foreign number plates, will they be chased for payment? or get away without payment much as happens currentlywith speeding offences.
Brian
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