Ballast Bonus Invoiced on Other Than First Voyage

We need to be able to add Ballast Bonus to an invoice on another voyage than the first voyage of a TC contract.
Currently, the only way we could make this work in IMOS, is to use the XHIRE expense type instead of the correct BALLA type.
The problem here is that these amounts will be posted on wrong accounts, since XHIRE is set up to be posted on a different account than BALLA.
However, when we use BALLA as expense type, we can only include the expense on the first voyage under that TC contract.