Hello,
I would apply a portion of customer advance payment to customer invoice.
For example, I would like to spread the advance payment according the following template:
| Amount | Advance payment | Amount due by the Customer | |
| Customer order | 3000 | ||
| Advance invoice paid | 300 | 300 | |
| 1st customer invoice | 1000 | 100 | 900 |
| 2nd customer invoice | 1000 | 100 | 900 |
| 3rd customer invoice | 1000 | 100 | 900 |