Actually, invoice payments were due on the date the invoice was sent. We make allowances for people who may not have the funds to pay right away by setting a hard deadline, beyond which your order will be dropped if not paid. However, a little communication in that regard would be nice. A simple PM saying that you're still in, but need until X date to get the funds together would work. But when it's been several weeks since the invoices went out, and we haven't heard anything from someone regarding an outstanding invoice, we start to think that person simply has no intention of paying and begin to look for other ways to move the GB forward.