An action for damages for negligence, other than one to which section 11 of this Act applies, shall not be brought after the expiration of fifteen years from the date (or, if more than one, from the last of the dates) on which there occurred any act or omission—
This section bars the right of action in a case to which subsection (1) above applies notwithstanding that—
before the end of the period of limitation prescribed by this section.