Note: Partner billing rules are applied before Custom Price Books (CPB) in the Partner Generated Billing (PGB) Order of Operations

In Partner Billing Rules > AWS Support > Action “Charge at AWS list price” - this action calculates AWS support charge based on customer spend pre-CPB. 

https://apps.cloudhealthtech.com/partner_billing_rules/new

The Developer, Business and Enterprise Support Tiers are calculated according to this AWS public pricing https://aws.amazon.com/premiumsupport/pricing/