Need to change response uri in payload from http to https

Prior to implementing F5, the SharePoint server connected to backend server using http and the backend server would send url within payload back to sharepoint server, the url is http. Now with Client connecting to F5 via https, then F5 connecting to backend on http port 50000. The backend server sends message back to F5-Sharepoint with url using http. I need to catch that response and change the url in payload from http to https