Using 90,000 FF miles, I have booked a flight from IAH to Madagascar via CDG (AF) and returning Nairobi to IAH via AMS (KLM) for September. The leg that was not available when booking was from CRP to IAH.

When is it likely that seats on this leg will be made available? I know I will have to pay an additonal $150 to add it on and a RT ticket will only cost $132---BUT I prefer to have a seamless ticket in order to not fret about making connections at IAH when using 2 seperate tickets. OR, is there a better way??

Thank you for your help!
Jane