Conn. Gen. Stat. § 49-37a

Whenever prior to April 22, 1975, a bond has been substituted for any lien pursuant to section 49-37 , which bond was in effect on said date, the obligee on such bond may validate the lien for which the bond was substituted by serving, by registered or certified mail, upon the principal and surety on such bond a copy of the certificate of mechanic's lien which was originally filed, within ninety days of June 25, 1975. Any such lien not validated pursuant to this section shall be deemed to have been invalid and discharged as a matter of law.