I am not sure if this is a bug or if I have something set up incorrect. I have a user that is given access to an interface without access to the base. However her notifications will occasionally send her to the base which se of course does not have access too.
I have experienced this as well, some of my notifications will bring me to the interface and some will being me to the base. We only use the interfaces in our day to day, so I am not sure why it would send us to the base.
I think that notifications by default lead users in the base data. If you want to manage it and make it more customizable for used of interfaces you can develop your own notifications using Airtable automations and add there the hyperlinks for the correct interface page including the record id also, so the users will lead on the right view.
I would think with the new update where we can prevent users from seeing the base when sharing that it would be rather troublesome that notifications default to base. I am only mentioning this issue because it seems random what goes to base or interface.