I made a business class reservation using USAir miles from LAX to TLV on Turkish Air. At the time of booking, I was told that the Istanbul-TLV leg was only available in coach, but that I could call back and move up to the correct class of service if/when business class became available.

In one of my calls checking on availability, I was told that, in fact, per the Star Alliance program rules, I could not move up to the correct class of service without redepositing the miles (for $150) and then re-booking, subject to the entire itinerary being available.

Aside with being inconsistent with what I was initially told, is this correct? I of course asked to speak with a supervisor, who confirmed.

Three out of four legs are booked in business class. One leg is booked in economy, but I "paid" the full amount of miles for business class. Assuming that space becomes available, is there any way that I can convince USAir to put me in business class for the missing leg without paying the fee and, more importantly, subjecting myself to the possiblity of losing the whole itinerary when I try to re-book? Thanks.