(a) For the purpose of this title, completion of a work of improvement occurs upon the occurrence of any of the following events:
(1) Actual completion of the work of improvement.
(2) Occupation or use by the owner accompanied by cessation of labor.
(3) Cessation of labor for a continuous period of 60 days.
(4) Recordation of a notice of cessation after cessation of labor for a continuous period of 30 days.
(b) Notwithstanding subdivision (a), if a work of improvement is subject to acceptance by a public entity, completion occurs on acceptance.