Show / Hide the icons in the lower bar for the mobile application

I'm working on a mobile application with a subscription that has two flows:

1. Before logging in: where an unregistered user can browse the application and see part of the content
2. After the login: access to additional functionalities.

Now, in this case, my application uses a lower bar as a navigation medium. And the structure is the following:

1. The unregistered user has 3 icons in the lower bar
2. When the user logs in the lower bar, it changes and now has an additional icon along with the previous 3.

Now my question is:

• Is it correct to show / hide / change the icons in the lower bar depending on the status – pre-login / post login?

Some things to consider are:

• The application is B2B
• Using the vertical drawer as navigation is not possible (development problems)

Thank you