Is the new portal the same site my institution uses to access PSAT-related assessment and SAT score reports?

No. The AP Higher Education Score Reports portal is a different site, and access will be granted separately.

If you already have a College Board professional account to manage PSAT-related assessment SAT score reports, or other College Board services, you’ll be able to use the same account. However, your account will need to be granted access to for AP score reports.