Hi Dan,
I think you might have even replied on the old thread but they definitely did it over the phone, they sent me a link over live chat I believe to upload documents but it was done on the phone when I called within 20 minutes.
The copy on the website is wrong, it says it can take a “few hours” but “up to 24 hours” is hardly a few 
Also you mention your use-case and well that may be the case for you when buying a car, just because something isn’t common, it doesn’t - at least to me - seem like a great excuse for not fixing a very obvious flaw, especially when multiple other banks manage to do it