Having a backup strategy is almost useless if you don't also test it from time to time. The time to test disaster recovery is not in the middle of a disaster
Just store your posts on 10 relays, problem solved.
Chaos Monkeys FTW
This. And another often overlooked and key consideration is the RTO. It's one thing to have a good back up, and an entirely different thing to get the data restored in a timely manner. If you can't withstand the downtime, you may need to rethink your backup strategy.