When will the deposit option in Estimate/Invoices that we were promised be implemented?

When will the deposit option in Estimate/Invoices that we were promised be implemented?

We need to see actual progress with your software in order to stay on as a customer. We have been very patient. I am hoping that your management will do the right thing and start implementing what you guys say will be updated. I want to know when this will happen and not get the tiresome response of priorities that also do not get implemented.