Thanks for the helpful tip. I strongly suspect that Tesla will honor the original base price if one waits to make changes until delivery-notice time (and perhaps even if they don't). Based upon past experience, the most likely suspect as to why the price goes up right now when a change is made is far more likely dunderheaded programming than policy.
As noted above, the bigger risk is that options will rise in price between now and config time. I just want to change my paint color, so I would deem it not worth the risk to change it now. But if an option I wanted was advertised to go up in price dramatically I suppose one strategy would be to go to a Tesla store and ask them if the base price will be honored regardless. If answered in the affirmative I would request an email to that effect, then print out my current config, and bring those two pieces of paper to the store when notified my car was going to be produced.
