Hey there!
Why don’t you just use another canister for the backup?
Your data is already backed up by at least 7 nodes in the subnet. If you think something bad could happen to it, just flush all the data to another canister.
First, it is just more secure (7 nodes on IC vs. 1 EC2 instance on AWS, or even your personal pc).
Second, it can be done in a permissionless manner. For example, you could enable your users to backup (or even publish in a first place) their articles if they care about their persistance. You could deploy a personal backup canister for each of them (on demand and not for free), where they could store it.
Moreover, one day you’ll definitely come to a moment, when your single-canister setup is not enough to store all the data your app has. This way you could front-run this situation.