Activity as described in the preceding sentence having been commenced and not yet finished, unless abandoned, shall establish that a building or improvement is "under construction" for the purposes of Section 5 of Article XIII of the California Constitution.
Construction shall not be considered "abandoned" if delayed due to reasonable causes and circumstances beyond the assessee's control, that occur notwithstanding the exercise of ordinary care and the absence of willful neglect.
Ca. Rev. and Tax. Code § 214.2