Hi

We have just launched our new website. We have a payment method called Proforma Invoice. A proforma invoice is not an order as such, we need to change the subject of the email when someone chooses this method of payment.

So when someone selects Proforma Invoice at the checkout and goes through the checkout process, instead of the acknowledgement email having a subject of:

Order Confirmation no: 1 from ABC Company
it instead has a subject of:

Proforma Invoice form ABC Company
Is this easy to implement? If so, please could anyone help? I can follow step by step instructions.

Many thanks in advance