It is most likely that the E10 will only be introduced on the 95 Octane "Eurosuper" grade , the V-Power (or equivalent other brands) will remain as E5. If you continue to use this grade you will minimise problems.
I am no expert on the CVH engine, but the generally perceived wisdom seems to be the engine will cope fine with E5 and E10 , for Morgans it is the carb, fuel tank, lines , and pump that could possibly be more affected.
I think there are various brands of "pacifiers" available which will limit the solvency of ethanol (and other non-hydrocarbon fuel constituents) which are used in vehicles which are laid up over long periods. George mentions one of them above.
I think the general advice is not to panic and change the fuel delivery system just yet.
