The challengers are not related to the Segments. They are just spread out through the indoor season the first one of the year being I, and the last one being VI.
Their are 3 Endorsers. Endorser I qualifies the winner for Super Segement 1. Endorser 2 qualifies the winner for segment 2 super and segment 3 is the same.
Lastly the Prince serious is an independent group of tournaments run by Judy and they are numbered in order of the time they take place. They like the challengers have nothing to do with the Segments.
I hope this helped.