Just as a warning for anyone taking the ferry or eurotunnel in the next few days, you need to build in at least an extra hour driving to reach the port.
We came back last night, driving through Belgium towards the Channel Tunnel. When we got to 2km from the French-Belgian border, we hit a traffic jam and it took an hour to progress 3km.
The police were filtering the traffic down to one lane and then diverting traffic off the road and around a roundabout so that they could do a visual check. The army were there too, with guns.
That was at 8pm on a Thursday evening, but they'd been doing the same thing when we arrived into France a couple of weeks earlier at 8am on Wednesday morning.
When we got to the tunnel, it was obvious that there had been big delays earlier and there was another very slow part when it took about 5 mins to check the passports of each car at the UK border. (I had plenty of time to count the cars and calculate the average).