This page provides an overview of the ways you can upgrade your Cloud SQL instances.
Upgrade in place
Upgrading and downgrading in place can be easier and less error prone than other ways of changing the edition, infrastructure, or database version of your Cloud SQL project. In many cases, you can initiate in place changes by editing your project's configuration in the Google Cloud console.
When you upgrade from Cloud SQL Enterprise edition to Cloud SQL Enterprise Plus edition to gain access to the performance enhancements and other benefits of Cloud SQL Enterprise Plus edition, your underlying infrastructure is likely to change. The upgrade includes moving to a different processor and to different storage, which can give you better price-performance, but which may come at a higher cost.
You can always choose to downgrade in place, from Cloud SQL Enterprise Plus edition back to Cloud SQL Enterprise edition if you would like, although this can require some downtime.
For more information, see: