How to Share Apple One Family Cloud Storage

Hello! I am the manager of my family share account. We recently upgraded to the Apple One Family plan with the 200 GB of iCloud storage. I am looking to share that with the rest of my family group however my dad has the 50 GB iCloud+ subscription and is sharing that with our family. (I don’t use it but others in our group do.)

What is the best way to go about this and have the least amount of “downtime” with the iCloud subscription? My best guess is that my dad has to stop sharing his plan and then cancel his subscription but I didn’t want to do without knowing that the 200 GB Apple One subscription would kick in right away.

Thank you in advanced for any and all assistance!