Expected behavior for family sharing

I’m testing family sharing on subscriptions and IAP in sand box.
 

I have an IAP that unlocks a lifetime access to the app and if users that are in a family sharing group purchase it, other members of the group are able to access it via restore purchase.

However, if a member subscribes to the monthly membership, they get access to the app through the lifetime IAP, but are also charged a monthly subscription. When they sign up for a subscription, it creates a new alias.

I understand that sandbox environment can be wonky but I’d like to get an idea of the expected behavior in prod from those who have tested this previously.
 

1. What’s the standard way for users to download a family shared app? You cant access Settings > Your Name > Family > Subscriptions with a sandbox account.
2. Is it expected for users to be charged a monthly subscription even though they have access to a family shared IAP?

Thank you!