1. By either consenting birth parent for any reason for up to seven days from its execution; however, such seven-day revocation period may be waived in writing at the time of consent provided that the child is at least 10 days old and the consenting birth parent acknowledges having received independent legal counsel regarding the effect of such waiver. In the case of two consenting birth parents, the waiver by one consenting birth parent shall not affect the right of the second consenting birth parent to retain his seven-day revocation period. a. Such revocation shall be in writing, signed by the revoking party or counsel of record for the revoking party and shall be filed with the clerk of the juvenile and domestic relations district court in which the petition was filed during the business day of the juvenile and domestic relations district court, within the time period specified in this section. If the revocation period expires on a Saturday, Sunday, legal holiday or any day on which the clerk’s office is closed as authorized by statute, the revocation period shall be extended to the next day that is not a Saturday, Sunday, legal holiday or other day on which the clerk’s office is closed as authorized by statute. b. Upon the filing of a valid revocation within the time period set out in this section, the juvenile and domestic relations district court shall order that any consent given for the purpose of such placement is void and, if necessary, the juvenile and domestic relations district court shall determine custody of the child as between the birth parents.