Imho...no chance of six, 5 BEING "turn up on the day" FARE PAYING PASSENGERS sailing in a BRe, at sea, in highly tidal areas.
There is a user on here who does something similar though? Perhaps they can advise?
Further.
Not that i am disagreeing in any way with GWs excellent advice, above, but...
CE plating sometimes seems perhaps to be something about as "scientific" as the RYA SWYTC handicapping system?
(See my concurrent whinge on another thread hereabouts!).
As much art as science?
My own BREx is plated Cat C for six persons. 540 kg. See attached!
I recently viewed a BC 26, also plated for Cat C, 6 persons, but in that case, six persons plus baggage totals 600kg. Cockpit much bigger than my BRe, as is the whole boat!
My 9ft Tehri tender (a very small plastic dory) is also Cat C plated, albeit for "only" two. You'd be hard pushed to physically fit/float more than two.
I was interested in Cat because (as prev discussed on here) my local race organising authorities were baulking at allowing my BREx to compete in a Coastal race series (limits between Plymouth and Falmouth), as it was "only Cat C plated".
Perhaps to cross reference my two current posts, the Django 7.7, a 25ft bilge keeler is CE Cat A (Ocean...self sufficient) plated...in France...
OP. However, I'm sure "The authorities" , not to mention your insurance Co would take a very dim view of any perceived overloading/ misuse etc, especially with fare paying passengers.
Given the above, common sense needs to prevail.
This not a criticism of anyone, yard etc. Just take it all not necessarily as gospel, and CE compliance is most definitely not some sort of get out of jail free card.
...and don't start me on "wheel marked" marine equipment