I'm glad there are so many people interested
The plan will be something similar to the following:
Portsmouth people: gather by the lightship from 1015 ready to leave by 1030.
Head to Calshot to meet those coming from other areas of the Solent at 1100.
If the weather is nice: Head to Cowes, for flasks of coffee/something stronger on the quay in the glorious sunshine. Proceed to Yarmouth, arriving aprox 1200.
If the weather isn't nice: Proceed slowly to Yarmouth.
Have lunch at the Kings Head (this may take a while!). Leave Yarmouth at aprox 1430, head for the needles for blasting around and lots of photos!
Head for Portsmouth at aprox 1530, returning by about 1630.
Of course, the above is open to suggestion/amendment! As usual, this will be a casual, fun cruise, not a race, so should be suitable for all sizes of boat as long as the weather is OK.