Timing is everything. If it’s the main French holiday weekends in the summer (16/17 July & 13/14 August are especially poor) then you may be delayed.

To be fair, it’s still not as bad as the M1’s going to be the Thursday before Easter.

It depends on where you’re starting from.
If you’re fresh when you get to Dover, take the Chunnel.
If you need a break and a stretch, take the ferry.

For me it’s 200 miles to Dover so I like the longer break & the chance to get out of the car that the ferry gives.

Nickf – it’s going to be next Wednesday.

Always go by ferry to France and tunnel back. Being on the ferry ads to the sense I am going somewhere. Train on the way back as I just want to get home by then.

Next Wednesday? You’ll (just) miss the July motorway queues then!