Tilly, I found that starting with this clue and by highlighting/refining the "key" features in searches on t'internet put me in the area almost right away.
" . . . we head to the shoreline, from where we can see an island. We could reach it at low tide, then she could then snap its 66ft lighthouse."
From memory, i think I remember reading they get around 6 to 8,000 entries a week.
I enter sometimes but not every week, I am only about 30 miles from Bath so not interested. Recently they seem to be a lot of UK breaks
A number of the prizes featured holidays outside of the UK which included flights with Monarch Airlines. Since that company went into administration in 2017, perhaps this may have had an impact upon the selection offered?