Any employing unit for which services that do not constitute employment under Section 631 are performed, may file with the director a written election, agreed to by both the employing unit and the individuals in its employ specified in Section 631, that all such services performed by such individuals in one or more distinct establishments or places of business shall be deemed to constitute employment by an employer for all the purposes of Part 2 (commencing with Section 2601) of this division. Upon the written approval of the election by the director, such services shall be deemed to constitute employment subject to such part from and after the date stated in the approval. Sections 704 and 707 shall apply to elections under this section.