upgrade RDS PostgreSQL12 to PostgreSQL15

A few years ago I built a Metabase on RDS on AWS.

I need to upgrade RDS PostgreSQL12 to PostgreSQL15.
Will Metabase work without problems?

Please let me know if there are any points to note or settings that need to be changed.

I am assuming you're referring to the application DB of metabase right? Which is PostgreSQL? Metabase should work without issues. That will also depend on what metabase version you're running, on what version are you?

If you keep with versions then Metabase supports the oldest supported version of PostgreSQL through the latest stable version

ありがとうございます。参考にさせていただきます。