Spend the extra 20 bucks (OK, $14 dollars US and about 9 pounds sterling) and don't restrict yourself to any 3 day period for goodness sake! Heck, a cheap lunch and a pint will cost about the same
. Additionally, I would be willing to bet that any saltwater fishing that you do will not require any special access as it will most likely be with another forum member or well known public water.
Just thinking out loud.