This is the end. Off to the tunnel and then home. No hold ups on either the crossing or the M20/M25 apart from dodging the holes and bumps on both. The Highways Agency, or whatever they are called now, should be ashamed of the condition that these two roads are in. Home 4 hours 30 minutes after leaving the tunnel, which is possibly a personal record, although the watch, the GPS, the vehicle clock, and the radio all seemed to operating in different time zones, so who knows.
My theory that many people are avoiding the Dartford Crossing these days because of the idiotic means of paying for it, and the repercussions if you forget, seems to be holding up. The .gov.uk payment site is also useless.