Enforcement Law for Part IV, Family Law of the Civil Code Article 6

A person who got married before the coming into force of the PART of FAMILY of the CIVIL CODE, may not only apply to the provisions of Article 1004 of the CIVIL CODE, but may also adopt the statutory regime [of the matrimonial property] provided in the PART of FAMILY of the CIVIL CODE as his contractual regime.The provisions of Article 1010 of the revised CIVIL CODE shall also apply to the persons who got married after the coming into force and before the revision of the PART of FAMILY of the CIVIL CODE. The period set forth in the Subparagraph 5 of the said article expires if it has expired before the revision; if it has not expired, the period shall be reckoned with both the time elapsed before and after the revision.
中文原文 民法親屬編施行法第6條
民法親屬編施行前已結婚者,除得適用民法第一千零零四條之規定外,並得以民法親屬編所定之法定財產制為其約定財產制。
修正之民法第一千零十條之規定,於民法親屬編施行後修正前已結婚者,亦適用之。
其第五款所定之期間,在修正前已屆滿者,其期間為屆滿,未屆滿者,以修正前已經過之期間與修正後之期間合併計算。

English translation for reference only; the Chinese text prevails. Not legal advice.