One feature that I wish was supported in RDS is to migrate from a MySQL engine to Aurora engine without having to create new database instance at all. It looks like Amazon DMS makes this process easier, but since Aurora is fully compatible with MySQL, I don't see why I have to create a new database instance and point my application to talk to the new server when Amazon DMS could do this behind the scenes on the one I already have.

Or am I allowed to set the source and target databases to be the one and the same?