Maybe I'm looking at this wrong. Do we know when young Jolyon left his family? I was under the impression that June never knew young Jolyon as her father, and that old Jolyon pretty much stood in that role. This is what surprised me about involving young Jolyon at all in the process, because I thought all contact was cut off between father and daughter, so why is he now taking an interest. Just seems odd and overstepping to me, somehow. And I do hope that June doesn't return to Bosinney. She's so young to settle for someone so wishy-washy and inconsiderate.
I'll have to think on this some more. It's a very interesting set-up, in any event.