It is possible for XCF to skip notification of certain events when they are superseded by later events. This allows XCF to present only the latest information to the group user routines. For example, a member might join a group and then change its user state value (through IXCSETUS) within a very short time. XCF might not be able to notify the group user routines of the member state change before the user state change occurs. In that case, XCF skips the member state change notification and presents the user state change notification. The group user routine can then infer, if it needs to, that the member state change occurred. (Only active members can issue IXCSETUS to change their user state field, so the group user routine can infer that the member became active.)