For owners travelling from the East for Japfest, we've alternated North or South of the M25 depending on who's joining where with the the aim of the usual larger meeting point at Cheively services (J13 IIRC) on the M4.
Over the Northern route there is South Mimms as a meeting point, where A1 \ A10 \ M11 \ A12 joiners can meet - added bonus of a couple of tunnel runs
Using the South there is now a new services area between J9 and J10 where those south of the Dartford crossing could meet.
From the who's who list it looks like the following are heading in from the East ...
Silver Surfer
L696ULO
Duncan
Senninha
Britlude
Any others wanting to convoy across?
Once we know who and from where (general area rather than specific address), we can decide north or south and work timings backwards from the larger M4 meet. We can also inf=dicate timings aloing the M4 so others can join up en-route if you wish.
If we can co-ordinate this with the SW convoy and those coming in from the Norht & South, we can then try to arrive in as a large convoy to Castle Combe
Regards, Paul