Definitely do the backup early on, and make sure you take regular backups - also ensuring it's backed up off device. You don't want to be spending countless hours building a config - especially with dashboards and then lose the lot because the install got corrupted after a power outage or dodgy update.
I do my backups outside of HA using proxmox snapshots. I absolutely love the ability to do a full restore in a couple of minutes, it's saved my bacon a few times when something catastrophic has broken during update. Most recently ZHA was failing to start, which would mean lack of control of lights and switches around the house. The WAF goes down very quickly when something simple like lights fail to work. Rather than spending hours troubleshooting, I can just restore it in a couple of minutes and deal with it later.