the whole itin is way less than the # segments limit:
TPE-HKG-LHR-MIA-JAX/JFK-HKG-TPE, i.e. 6 flight + 1 surface segments
in fact, I just double-checked, this particular ticket was actually issued around Feb/Mar this year with the first flight in early Mar.
so I think my proposed itinerary change should be ok according to the rules, right ? thanks a lot.