(a) When a city, county, or city and county assumes responsibility for the enforcement of parts 2.1 and 2.3, of division 13 of the Health and Safety Code, and Title 25, California Code of Regulations, division 1, chapters 2 and 2.2, cancels its assumption of such responsibility, or has assumption approval cancelled by the department during the permit renewal year, collected for the annual permits to operate, other than state fees pursuant to subsection 1008(a)(4) of this article, shall be returned in an amount equal to the percentage of the year remaining before the permits to operate expire.

(b) The additional four dollar ($4) per lot fee collected for park maintenance inspections also shall be remitted in an amount equal to the percentage of the year remaining before the permits to operate expire.