Really don't get this one.
Completed first grid fill relatively painlessly then floundered understanding what Harribobs means you to do next.
I'm assuming the grid refill takes place using the plain rather than cycled across solutions (though he doesn't say this).
If you refill using the plain across solutions in presented clue order (ignoring the bars as answer separators) you get 114 filled cells followed by 30 unfilled cells starting at row 10, cell 7.
This can't be right since it seems the 30 letters of the two extra destinations have to be scattered throughout the grid with the first letter of the first extra destination sitting at row 1, cell 1 and the fourth letter of destination 1 at row 8, cell 1.
The first letter of the first destination can be any of the 26 letters of the alphabet so how come a previous post has narrowed it down to just one of 4 letters?