There is only one window seat left on my flight in CW and it's frustrating that the website can't confirm my seat change. When I called, the agents could see I'm a ruby (otherwise known as a BA rube?) but so far the agents have given wrong advice. The first agent said that since the flight (7 days away), I must wait until tomorrow, or T-8, because they count both today and the date of the flight. The next agent said I need to wait another 8 hours and then I should be able to do it online. Hold times are now running 20 minutes. Any advice, or route to get a more knowledgable agent on the phone?

I've used both the Safari and Chrome browser but same result.