I've now spent over 7 hours on the phone and through online chat. This is farcical, why on earth MS would admit to the problem, offer a free upgrade but not inform any member of their support staff how to deal with it is beyond me.
Ive been passed to commercial support, who say "yep, we know all about this... You need to speak to the Answer Desk account & billing dept" for the whole sorry saga to start over.
I got as far as giving my product key, then "oh, we can't do this" we'll send an email. I got an email saying it would take 24-48 hours to locate the account Visio is activated against (it's standalone, activated with a product key, so don't think it'll
show anywhere!) - it's now been well over 48 hours and nothing.
Its the the stupid things like this that make you realise how backwards MS are in their customer service, and what generates bad will. This is where Apple win time and time again.
Windows 10 and Office 2016 are great products, all we really want is to be able to claim the upgrades we are entitled to - I simply can't understand why this is such a big problem.