When assigning a role to a user, you can specify an activate date and a deactivate date. Role-assignment work-item requests are created when the assignment is made. If a role assignment is not approved by the scheduled activation date, however, the role is not assigned. Role activations and deactivations take place a little after midnight (12:01 AM) on the date scheduled.
By default, only Business Roles can have activate dates and deactivate dates. All other role-types inherit the activate date and deactivate date of the Business Role that is directly assigned to the user. Waveset can be configured to allow other role types to have directly assignable activate and deactivate dates. For instructions, see Configuring Role Types.