; and (4) a modernization of the file to bring it up to current investigative standards to the extent it would help develop probative leads. (c) Reviewer The person or persons doing the review required by subsection (a) shall not have previously investigated the murder at issue. (d) Acknowledgment The applicable agency shall confirm in writing receipt of the request provided for under subsection (a). (e) Prohibition on multiple concurrent reviews Only one case review shall be undertaken at any one time with respect to the same cold case murder victim. (f) Time limit No later than six months after the receipt of the written application submitted pursuant to subsection (a), the applicable agency shall conclude its case file review and reach a conclusion about whether or not a full reinvestigation under section 5 is warranted. (g) Extensions (1) In general The applicable agency may extend the limit in subsection (f) for periods of time not to exceed six months if said agency makes a finding that the number of case files to be reviewed make it impracticable to comply with said limit without unreasonably taking resources from other law enforcement activities. (2) Actions Subsequent to Waiver For cases for which the time limit in subsection (f) is extended, the applicable agency shall provide notice and an explanation of its reasoning to the designated person who filed the written application pursuant to this section. 3. Application Each agency shall develop a written application to be used for designated persons to request a case file review under section 2. 4. Notice Each agency shall provide notice of the rights under this Act to designated persons as soon as is reasonable after being made aware of a murder. 5. Full reinvestigation (a) In general The applicable agency shall conduct a full reinvestigation of the cold case murder at issue if the review of the case file required by section 2 concludes that a full reinvestigation of such cold case murder would result in probative investigative leads. (b) Reinvestigation