Invoice Approval auto approve criteria in parallel

Summary

Need help creating auto approve rule for approval group in parallel

Content

Hello, 

My Invoice approval process is Group A approves all invoices but if the invoice amount is greater than $500,000 then it needs to be approved by Group B after Group A (both are first responder). I need help figuring out how to set up the Invoice Approval Rules to auto approve for Group B if the invoice is less than $500K 

So far, I have Group A in SingleParticipantParallel with no other conditions than an Invoice was submitted. Then, sequentially, I have Group B in SingleParticipantParallel with the condition for approval that the Invoice Amount is same as or more than 500,000 in a custom InvoiceApprovalRuleSet Rule. In order to skip going through Group B, do I need to create a rule to autoapprove Invoice Amounts under $500000? Or if the Invoice Amount is under 500K, does it automatically skip Group B?