From the Introduction: "This document provides the standard procedures that staff from the Department of Homeland Security's Federal Emergency Management Agency (FEMA), FEMA contractors, and other organizations that partner with FEMA are to follow for processing new and revised Flood Insurance Study (FIS) Reports and Flood Insurance Rate Maps (FIRMs). Specifically, this document provides guidance on project deliverables made during the Post-Preliminary Processing (PPP) phase of a Flood Risk Project. The PPP phase is the period of the Flood Risk Project from after Preliminary Issuance to the Effective Date."
Guidance Document 55
U.S. Federal Emergency Management Agency: https://www.fema.gov/