1. A method of establishing an availability check framework, comprising: defining a plurality of inclusive rules, each inclusive rule specifying at least one of a location and a product to be checked for availability; and defining a plurality of exclusive rules, each exclusive rule specifying at least one of a location and a product which is excluded from being checked for availability; wherein the plurality of rules are provided for selection within an availability check procedure, and further wherein at least one exclusive rule of the plurality of exclusive rules comprises at least one indication which is representative of at least one time period in which the exclusion of the at least one location or product specified in the respective exclusive rule is valid.