Please post the proper Composer CLI commands for upgrading Mautic 4x

The documentation on the Mautic website for installing and upgrading Mautic using Composer is confusing and, if followed, causes Mautic to delete the configuration file, knocking Mautic offline. We had to restore from the backup because of this.

What are the exact commands to upgrade Mautic via Composer at the CLI?

As I understood one other posted that outlined this - the fact that config gets deleted is something that will not get addressed before mautic 5.x.

Before each update always of mautic, no matter how small please backup full database and source