Requested a TiVo upgrade to 360, got sent a remote instead!

That's correct. If they have sent you a controller the up/downgrade* is just a firmware one to the same device. 

*opinions vary. 

There will be an app on the box for installation. If you can do not install for as long as possible because you will lose everything and the box will not work. As you can read there are loads of issues. I downloaded yesterday and have nothing as it is frozen on the welcome screen even though after 4 hours I got it all working. Today it froze and no matter where I switch it off it stays. So I am waiting until Tuesday to get an engineer who will likely just give a new box

Hi richardsmiff, 

Thanks for taking the time to contact us via the Community. It's lovely having you on board with us in the Forums. ⭐

We'd only send a remote if there is a V6 box on the account. The upgrade is software update rather than a new box. Once you've received the remote, you can find help to upgrade the box here. 

If you have further issues, pop back and let us know. 

Many thanks,