After a teacher who is duly employed by a district qualifies and is selected for participation under a career plan established under sections 168.500 to 168.515, such teacher shall not be denied the career pay authorized by such plan unless he:
(1) Is dismissed for cause as established under section 168.114; or
(2) Fails to maintain or renew any certificate required by the department of elementary and secondary education; or
(3) Fails to maintain the performance level as required for the attainment of the career stage as set forth in the plan effective in the local district as provided in section 168.500; or
(4) Fails to complete professional responsibilities required for the attainment of each stage; and
(5) Has exhausted all due process procedures provided by subdivision (6) of subsection 2 of section 168.500.