There was this image from @John_Pateman:
Continuing the discussion from Beginner question about symbols and footprints:
J1 does not have to be a screw terminal, and to the left side of the schematic does not need to be just a floating single part.
My idea is that a hierarchical sheet could be assigned a separate hierarchical PCB; Main Board, Daughter Board_0, Daughter Board_1, Daughter Board_2.
Q1 could be in fact a SMD device, with supporting components, on a seperate connecting board (Is why it has always seemed to me that some of these connections should be P1, and not J1.
ON EDIT: Attempting to Clarify