Using a managed database solves this problem, so there's that an option.

If you self host your DB, if the data is on block storage you can at least spin up a new instance and connect that storage device onto the new instance with a short period of downtime. This is usually a satisfactory level of downtime for an event that doesn't happen too frequently.

What I like about the above is it'll work with any database and avoids needing to even think about performing real-time or near real-time replication with multiple writers.

There's also the scary truth that there's a ton of stuff out there where compliance requirements aren't enforced. I'm not saying it's a good idea but you can choose not to upgrade too. This is a risk assessment you'd need to do. At the very least if you go down this route, please make sure your server doesn't even have a public IP address. If it's super locked down, that doesn't mean it's safe but you'll want to limit the number of attack vectors as much as you can.