When we have a fixed price project and make an on account transaction, invoice status is "Chargeable". When user makes an invoice proposal and post it, Invoice status is "Fully invoiced".

If user credit the line:

Select for credit note, make a new invoice proposal and post it > Invoice status is "Chargeable"

With invoice status "Chargeable" user is not available to finish the project.

It would be good if there is an option select on account for credit note to result in "Fully invoiced" status.