/AVAILABILITY= code | CONSTANT=integer
Specifies a license unit code that corresponds to a License Unit
Requirement Table (LURT) or to a constant value. If your PAK
supplies an availability code, you must enter the code exactly
as it appears. The current codes are A, B, C, D, E, F, G, H, and
I. If your PAK specifies the keyword CONSTANT, then you must also
specify the integer value from your PAK. PAK issuers determine
the value for this element.