Good Morning. As a writer, we've all wondered when we finish the first book if we have "enough" to turn it into a series. As soon as I found Penny and William (from THE LADY'S MASQUERADE) I wanted to do one. I had a broad scheme and fleshed out the story lines from the other three books I was going to write. (Back then it was only three.)
However, I found doing research one day, my storylines were not going to work. The months I had planned to use in my storyline for the THE CAPTAIN'S LADY and THE LADY'S FATE were all wrong. Parliament was not in session, and that played a key role in how my men were going to be in London. So I had to scrap the idea and come up with another plan.
There was also the problem of the Prince Regent. His ascendency to the throne did not take place until February 1811. Also, his sister, Princess Amelia passed away in November of 1810, which also played a part because the country went into national mourning.
Hmm...what was a writer to do? So I decided that I would do what I like to call, a "wrap-around" or "over-lap" series. All my books overlap each other, and wrap around. The characters, the plots, and storylines mesh and blend, so all the stories intertwine.
To break it all down in simpler terms.
THE LADY'S MASQUERADE March 1810 -- September 1811
THE LADY'S FATE May 1810 -- June 1811
THE CAPTAIN'S LADY September 1810 -- February 1811
THE DUKE'S DIVORCE March 1811 -- July 1811
THE EARL'S ENIGMA June 1811 -- October 1811
This overlap solved several problems at once; allowed me to combine characters and storylines from one book into another, kept me from having to do uncessary research (and therefore allowed me to write more), and kept all the characters fresh in my mind. They're all friends and friends lives do tend to overlap.
Tell me, have you ever read a series such as this -- when all the books continue during the same time frame.