The main problem last year was the return leg with the queue around the junction of the A28 with the A13 - at the bottom of the the last map above. The "solution" (which could turn out to be just another traffic jam!) suggested was to exit from the A28 earlier - south of what is shown on the bottom map - and approach Rouen on the old N138.
However this is route is just as likely to get jammed! I've been in similar situations before - Hit queue on M6 north of B'ham. Off on to the A34. Hit queue. Off on to some B road. Hit queue. Off on to side road .... etc etc... Before you know it you driving down a farm lane with grass down the middle! Which then crosses over the motorway on a bridge. Only for you to look down and see a free flowing motorway. Tomtom makes it too easy to get into this pickle.
However - I encourage everyone to turn off the A28 (and I'll stay on it and fly through the peages
)