+1 to most all responses in this thread.
At some point, a manufacturing operation has to lock down what they're building. 'Finalize' is pretty clear and I think most agree it's not just the point at where you cannot get your deposit back - it's the point where you have finalized the configuration of the car. (And let's not revisit what Tesla said regarding the superchargers. There are a number of people on this forum who publicly agreed with the interpretation Tesla thought was clear.)
Tesla has been kind enough, when they were first ramping production, to change a few final configurations. But anyone involved in a manufacturing operation can tell you that changes, even BEFORE something hits the floor, causes work. Stock on hand, changes to the MRP system, scheduling, paperwork for the specific item (travelers in my business) take time to change. Multiply your *simple* request by 10 or some other number and they miss production goals for the week.
At some point Tesla needed to say 'no, not going to happen, finalize means finalize' or put the business goals at risk. As an investor, I hope this is the lockdown on changes. With enough yelling publicly on the forum, maybe you'll get your change. But I hope not. It's time for Tesla to be a manufacturing company.
Here's a question: Would you be willing to pay for the costs the change incurs in their workflow? (And before you say 'yes!', I can tell you that metrics I've run in the past show the simplest change (prior to production, parts not committed, parts in stock, etc.) show a pretty pricey tag.)
I'm sure you're disappointed and I'm sure you can't understand why, if you want to spend more money, they don't just say yes. The specialist's reported attitude (I'm sure unprovoked) was unacceptable. But out of kindness, think how you might feel if you'd had ten calls in a row asking for just a small change & a company saying 'finalize is finalize'. What do you want him to say?