@staticmethod
def interfaces_roles_change_and_tree_remains_active(interface:
    'TreeInterfaceUpstream') ->None:
    """
        Interfaces roles change (NonRoot->Root) AND
        Tree was Active and remains Active
        """
    interface.logger.debug('interfaces_roles_change_and_tree_remains_active')
    interface.send_i_am_no_longer_upstream()
    interface.send_my_interest()
