I use that boat on a regularly basis (5 times in one week once), during the daytime sailings its just under 6 hrs sailing.
When you get to Portsmouth pull on the weighbridge and tell him your going to Caen, he will then give you a weigh ticket then pull forward into a lane marked up above for Caen. Put hi viz jacket on then book onto the ferry at the office behind you slightly to your left, ask at the weighbridge and he will show you if your not sure and remember your CMR and Passport.
You will get a credit size card this is your cabin key ( 2 drivers to a cabin and they have always paired me up with a fellow brit ) and gets you half price off the food ( A tip when getting food if you drink wine, the small red wine I think called Dauphin is buy one get one free, the other small bottles maybe the same but thats the one I get ) Coffee is free on the ferry for truck drivers when you show your cabin key.
When you get out of your truck remember which stairs or lift you have used and what level you are on, makes it easier when looking for your truck when you arrive.
Remember when you get off your one hour ahead and sailing times are always at local time so your 14.45 return sailing is at 13.45 UK time and leave your tacho on UK time.
When you get on the boat if you have a digi tacho put it on ferry mode especially if you are counting the crossing as part of your overnight rest period. When you park up remember to put the end country to “F” or whatever country you are in.
When you get off the boat just follow the exit signs keeping the wired fence to your right, when you get to the passport control just drive slowly passed it as there is usually no one in and then again slowly to the customs booth and barrier (again usually no one in ) and the barrier with raise automatically. The speed limit out of Ouisterham ( that is actually where the ferry docks, Caen is approx 15kms down the road) is 30kms per hr until you get to the first roundabout. If you are using a sat nav an idea might be before you leave the dock add your current position as a favourite to make your return journey easier for you, I always do this at a new ferry terminal.
If you are looking to fuel up in France there are not many fuel stations on your route, there is one just 3kms out of the ferry terminal which you will pass, that is an Esso station and is an unmanned station and only takes cards, Esso and I think UTA, DKV , the next station down is on the A84 approx 1.15hrs drive from Caen and that is a Shell station just off the autoroute. Your boss may have other fuel cards and a list of stations, I think there is a Total garage again just off the A84 approx 2.15 hrs drive just south of Avaranches, that is of course you go that way.
I’ve had a look and if you take the A84 down to Fougeres then the nationals to Laval there are no motorway tolls. Leave the docks following the signs for Caen, over 1 roundabout, pass the Esso station over the next roundabout and you are then on a dual carriage way to the Caen ring road then follow the signs for Cherbourg, Rennes, St Malo, when you then get on the ring road just follow the signs for Rennes and St Malo A84 E3 and NOT the Cherbourg signs, when you get passed Avaranches follow signs for Rennes, Fougeres and NOT St Malo, leave the A84 AT junction 29 for Fougeres you will then pick up the signs for Laval. Junction 29 is about 2.5 hrs from the boat and you will easily get to Laval in under 4hrs. Remember when leaving autoroutes abroad they don’t tend to have roundabouts like we do and some of the exits can have quite sharp bends on them so take them slowly.
Return journey is just the reverse and when you get back to the Caen ring road (periphique) just follow either your sat nat or the signs for the Car Ferry and when you pass the Esso garage to follow the TRUCK signs to the ferry and NOT the car signs, pull upto the barrier and a security guy will either lift the barrier and wave you through or come out and have a quick look under and around your truck for immigrants, then go straight on and another guy/woman will tell you which lane to park in, then go to the offices to the right and book in.
When you get off the boat in Portsmouth you cannot park up overnight to finish off your break but you can use the allowed movement of 1 hr to get somewhere to park, but if you have timed things correctly you should be able to get from Laval upto the ferry ship over and get back to Heathrow in a 15 hrs shift.
Hope this helps and if any more questions just ask.
Paul