Actually, I probably would sub-head it like you said if it was necessary to do so. Though I think I was speculating on a first-person POV shift. Neither of which I've done in that way.

Actually, now that I think about it, if I was to write what you just did (hehe... goats... and sated?? LOL) I wouldn't demarcate the shift at all. I don't seen any reason to tell the reader I'm shifting from one third-person limited to another; if I can't make that shift apparent, or construct it so there's a chapter change as well, I shouldn't be doing it.

Philip K Dick did this all the time.