One downside to the spinoff focusing on these characters in their younger days is that the actresses who brought them to life in Bridgerton Season 1 presumably won’t appear in the series, unless it is told via flashbacks, there is a flash-forward, or they take over narrating duties from the venerable Julie Andrews.
They will presumably all return for the next seasons of Bridgerton, however.
Creator Chris Van Dusen will remain on board Bridgerton as showrunner through the end of Season 2, with 13-year Shondaland veteran writer/producer Jess Brownell taking over as showrunner for Seasons 3 and 4.