Risk Rating new business account

Hello, I am trying to verify something and see what the practice in other banks is.

I perform Business Risk Assessment for every new business that opens accounts with our bank. There is a Business checklist (the due diligence questions) that the Customer Service Representatives fills out at account opening. Later I review the checklist and all the supporting documentation (signature cards for CIP, Articles of organization or business certificate, OFAC check, etc.) and determine the Risk Rating for that customer.
My question is what do I do when we have a new (or replacement) account for a well-established customer with previous accounts opened years or months ago? Do I gather all the documents again, do I just request a business checklist for the new account or do I skip all those steps and just mark the account “new account for existing customers”? Keep in mind that I am fairly new to the position and I don’t know how good of a review and rating they used to do here let’s say 6 years ago when the first account was open.
Basically do we risk rate a business on customer or account level?

Thank you, I appreciate any input that you can provide.

Customer level. Unless the line of business is completely new, that is.

Customer level. I would not perform a new formal risk assessment for an existing business customer because they opened a new/additional account.

Thank you!