Currently the password expiration feature is server-wide, this works if you are a single company or single domain and want to implement this for all your users. However, being a hosting company and having multiple tenants, a server-wide policy like this may not sit too well with some customers. 

We DO have customers that want this option to force their users to update their passwords. We would like to request for you to add this feature on a domain level. Also, a report that shows password age of each mailbox would be very useful.