Question About Retaining Domain Authority When Moving to a New Website

Hi everyone, I’m working on a project for a large organization that currently uses multiple subdomains for different locations (e.g., florida.organizationwebsite.com). One of these subdomains has a high domain authority, but I’m unable to edit or install plugins on it due to restrictions. The superuser suggested a solution: build a completely new website with a new domain and link the IPs of the existing subdomain to the new website. I assume this means some kind of redirect will be implemented. My main concern is this: if we move forward with this approach, will we lose all the domain authority tied to the current subdomain, including all the backlinks and SEO juice? Is there a way to preserve or transfer that authority when moving to a new domain? Would love to hear your thoughts or suggestions on how best to handle this from an SEO perspective. Thanks in advance!