Extension of period of notice.

The effect as to third persons of the filing of any such instrument for record, may, in all respects, including the preservation of priority thereof, be extended for successive additional periods, each not exceeding 7 years from the date of the filing in the office of the clerk of the circuit court, wherein any such instrument is recorded, upon the filing by the owner or holder thereof, of an affidavit identifying such instrument, stating her or his interest therein and the nature and amount unpaid on the obligation still secured thereby. Provided, however, that where a mortgage or other security instrument has been amended or supplemented one or more times and an identifying affidavit is so filed for record by the owner or holder thereof with respect to the original mortgage or other security instrument and mention is made in such affidavit of any instrument or instruments amendatory or supplemental thereto such identifying affidavit need not be filed with respect to such amendatory or supplemental instrument or instruments so mentioned therein and the effect of such amendatory or supplemental instrument or instruments and the preservation of any lien or priority thereof shall be extended along with the original mortgage or other security instrument as to which affidavit or affidavits have been filed in accordance with the requirements of this section.