spanzviewmaster

'Why doesn't the redemption/upgrade class I asked for appear?'

Anyone heard of POS. It stands for POINT of SALE. Everytime you make an availability entry or request a fare display, this little beauty comes into play and determines the parameters contained within the airlines response.
'Rules' set within each of the individual airline inventory systems control who gets to see what. This can run the whole gamut from everyone seeing everything, to very strict controls, whereby two people sitting in the same office, with terminals connected to the same system will get a different response to exactly the same entry made at exactly the same time. POS is one of IATA's protocols that enables an airlines revenue managment to control who can sell/buy inventory and at what price. Some of the basic rules are agent/city/country/currency etc. Note, not all systems use all rules however you can be sure that the majors probably do. This would be one of the main reason why when you request specific class availability of an airline (either direct or via a GDS) you may not get the response you want.
Another reason is that, depending on an airlines policy and fare rules, classes are blocked from display when not available and not allowed to be waitlisted. Remembering that there are a possibility of 26 single alpha chars and max 2 numeric chars and a space for each class in an availabilty display (without adding x number of combos of 2 alpha and 2 numeric chars), ie 104 spaces on the screen without flt number date bpt/opt. Try and read a screen with that sort of combo of flights on it especially if the systems is capable of building four flt connection routings. Its murder on your front end programmes that screen scrape.
Airline res screens normally have a much smaller display area than you PC (can't remember, but something like 62 chars across 34 lines down).