Since the AWB freight and handling costs will vary as the time passes, the system allows to setup the AWB Freight and Handling cost by time periods (seasons). This article explains how to do it.
Seasons do not have an end date. That date will be given for the Starting on Date of the new Season created.
The first Season will be created by default when a new company or location are created with a Starting On Date of 01/01/2014.