What is the double entry for Under Billing or Over Billing found in the chart of Percentage of Completion Method in a construction company?

Does the following double entry not come in case of under billing?

Debit: Due from customers for contract work A/C

  Credit: Progress billing A/C/ Under billing A/C

In case of over billing:

Assuming the following data:

Cost Incurred  

Contract price  

Progress billing  

To rectify this we will:

CREDIT: Progress Billing A/c with

DEBIT: Due to customer A/c with

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In case of under billing:

Assuming the following data:

Cost Incurred  

Contract price  

Progress billing  

To rectify this we will:

CREDIT: Due from customer A/c with

DEBIT: Progress billing A/c with