TeamDynamix Web API: TeamDynamix.Api.Users.GroupMember.EndDate

Unless explicitly stated on the documentation for a method, the accepted Web API call content types are:

Calls using any other content type (ex: text/plain) are not supported.

TeamDynamix.Api.Users.GroupMember.EndDate

The date after which the user is no longer available for scheduling and no longer required to log time.

DateTime Editable

This only applies to Users. Customers will always have this set to an empty date.