When posting the customer lines, the reconciliation account was always determined from the financial accounting section in the customer master record.
It was not possible to differentiate between transaction-related or billing document type related posting to the reconciliation account. Only ONE G/L account can be entered as the reconciliation account.
As well as determining the revenue accounts or sales deduction accounts via the condition technique, the reconciliation account can also be determined using the condition technique so that a completely different account can be determined via the billing type, for example.
If an account cannot be determined via the condition technique then posting is carried out in the reconciliation account from the customer master.
You can maintain account determination in chapter "Reconciliation account determination " of the IMG.