It's good to see a Kent (or more generally south east) based 400. It would be good if one could be established as an annual fixture (and perchance a National ride).
I did the old Invikta 400s when they ran out of Chiddingstone. The main things I remember are eating a ropy Chinese take away in Sittingbourne, getting lost at the end to the extent that I almost came in out of time, and a certain long-standing member mumping because his trike didn't fit through a motorway service station entrance (he had to ride up a dirt track from memory, as the A road had been reclassified into a motorway, and it got increasingly narrow at the top - his own fault for riding a childs bike
). And, I think, belting along the A2 in the middle of the night. If this gives the impression of Type 2 fun, it was.
Anyway, this one is on my list of possibles for 2019. Time has moved on so I suspect it will be a much polished route from Tom. I'm hoping to do it if I'm in the area, can wangle a weekend pass and have a decent build up to it over the spring.