Preliminary work was done on the first four episodes of a second season were began, but a strike caused them to cancel it and the footage was taped over.
A two-part short story, titled "The Spin of the Wheel", which covered the gap between them leaving Eaton Place and the start of this show was written by Alfred Shaughnessy and published in the TV Times just prior to the start of the spin-off.
When Thomas and Sarah left Upstairs, Downstairs (1971) they were supposedly married, but as this spin-off begins, it seems they never got around to it.