At present it would be quite awkward, and potentially have a negative impact on the application’s performance, to implement the kind of extra flow breaks behaviour you are asking for here, which is on the face of it entirely reasonable to request, of course. It’s not something we’ll be able to do soon.
I know that musical theatre works undergo constant revision up to and even beyond the first performance and so it is unavoidable that there will be cuts and so on, but you could probably save yourself some of the headaches by leaving the option to start a new flow in a new frame set until as late in the day as possible.