There are three available types of Billing Block for PGB (Partner Generated Billing) customers: Consolidated, Standalone, and Full Account Family.  

Consolidated:  This type of partner generated billing creates a single bill for all customer accounts within the Billing Block. Tax/VAT, reseller credits, AWS Support, and tiering benefits are removed from the generated bill.  RI (Reserved Instance) Float is recalculated based on the accounts present within the block and available usage, RIs (Reserved Instance) are applied on a first-come/first-serve basis.  Tiering discounts are reapplied and based on all combined accounts within the bill.  One PGB statement will be generated for all accounts within the Billing Block. 

Standalone:  This type of partner generated billing creates a single bill for each customer account within the Billing Block. Again, Tax/VAT, reseller credits, AWS Support, and tiering benefits are removed from the generated bill.  Here, RI float is not applicable since only one account exists in each bill.  Tiering discounts will be reapplied based on every single account in its own bill.  One PGB statement will be generated for each account within the Billing Block. 

Full Account Family:  This type of partner generated billing creates a single bill for all your customer accounts.  All costs are charged to the customer accounts except for reseller credits and Tax/VAT, which are removed from the generated bill.  One PGB Statement will be generated for the Billing Block.  

There is no limit to the number of Billing Block combinations that can be made.