Well, I was amazed at the volume of responses: over two dozen.
Three suggested that I stop and start over: one explained that some (many?) readers wait till a story is complete prior to beginning it.
One reader criticized my "introducing" swapping.
Another threatened to kill me if I stop (I don't think this was a serious threat).
So, Patrick and Rachel will be followed until the end of this academic session. But ... there will be complications.