Enter your idea

Revert the new standard bill template to the old layout so the amounts on the Invoices are net of VAT, and the poor people who have to process your subscription invoices don't have to waste time checking figures when subscriptions have to be recharged. It is already time-consuming when you have to deduct the subscriber discount.
Do you have an accountant or bookkeeper review the design before releasing it into the wild?
The other option would be to enable people to download a PDF of the old design, or better still, one in which any subscriber discount is already applied, as you already give the ability for that design in the customisable templates.