Originally Posted by
DownUnderFlyer
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Also what exactly do you mean with buying an extra leg? Where and for what? Do you want to go above 16 (which you can't)?
An extra leg can be purchased over and above the continental limit. i.e. you can have a 7th intracontinental leg in N/A and a 5th leg in the other continents.
The 16 segment limit still applies.
Presumably the OP is looking for GRU to somewhere else in S/A then connecting to NRT.