Onsite 365 Backup Repository is filling up.

I am using direct attached on premise storage for my backup repository.  That repository is getting close to being full, and I am having trouble understanding what next steps are.

I have 30 day snapshot retention enabled.

My concerns are around can I add a new repository that will continue to add new snapshots without having to start all over again and backup the entire 365 environment to that new repository?

Ideally if I create a new repository, after 30 days the old (current) repository should be expired and can be removed. But I have a feeling it doesn’t work that way.