openshift 3 to openshift 4 migration

Greetings everyone. So, we now have openshift 4 clusters for both prod and stg and I think (although correct me if I am wrong) they are all checked out and ready to handle apps. :) To move an app over: * stop all the apps pods in openshift3 cluster * Define any NFS storage that the app has in the ocp4 cluster. * change the playbook to use 'os-control01' and 'os-control01.stg' for copying the templates for the app to /etc/openshift_apps/ and running oc create to create the apps namespace, objects, etc. * change the proxies reverseproxy to use the ocp4 backend instead of os3 * add some metrics? * Profit Apps that don't have any NFS storage and don't have a DB could probibly be deployed in the new cluster and left running in the old one, then switched in proxies, but that won't work with things that have DB/NFS or other persistent state where we don't want the app running in multiple places at the same time. We need to determine how we want to migrate things however. Do we want a flag day where we schedule a big outage and try and move everything? Do we want a flag day for stg, but schedule outages for prod? Or do we want to schedule outages for prod, but do all the stg ones as our time permits? Are there any folks in sysadmin-openshift wanting to drive this? (Although we could likely use help from anyone to test apps as they move, help with announcements, etc). Do note that we have a lot more apps in stg (thing that haven't yet been deployed in prod). kevin