Which invoice grouping options are supported for item-based billing?

Summary:

We have configured Project Billing to support inventory item-based billing.

• In Scenario 1, when the bill plan includes the labor and nonlabor invoice formats with the ‘Contract Line, All’ grouping method, we can submit and approve the contract
• In Scenario 2, when the bill plan includes the labor invoice format with the ‘Contract Line, All’ grouping method, but the nonlabor invoice format with the ‘Contract Line Project/Task, Expenditure Category’ grouping method, we receive the following error. "The invoice format attached to the bill plan isn't grouped by contract line and the contract line is either based or has a purchase order number."