Originally Posted by JayhawkCO

To add another bit of info here, I was booking a JFK-JNB award, and I looked at tacking on a JNB-SHO flight at the end, but it raised the price from 88k miles to something like 111k miles, so it's bookable, but definitely seems like a "separate" booking. However, when I included a 4Z flight as my Excursionist Perk, that set of flights remained at 0 miles, so better value to redeem on 4Z there.