I thought I had carefully figured out the companion upgrade rules for elites on Delta, but yesterday a skymiles rep gave me conflicting info. I had thought that when you are an elite of any level, your companion can be upgraded with you so long as they are class U or higher. He told me that companion must be class K (i think it was K) or higher. Can anyone confirm this and also can anyone point me to where to find a list of all the classes in order of their price/rank for upgrades?