This is really Charlotte’s story . . .
And when Miss Heywood returns to the seaside resort town of Sanditon in the summer of 1820, nine months after Season 1, she discovers a whole new world. Simpson credits director Charles Sturridge, whose period drama work dates back more than 40 years to Brideshead Revisited, with the idea to create a promenade connecting town to beach where characters “would all walk right against the beach and the sea. It gives an opportunity for a beautiful backdrop and chance meetings.”
https://www.tvinsider.com/1034600/sanditon-season-2-filming-locations-charlotte-sidney-alexander-francis/