The 3DS Ambassador program, the free download initiative by Nintendo for customers who bought the console before the price cut, is now live in the UK.
For those that downloaded the system update before the close of the offer last month (simply asking you to to connect to the eShop to automatically download it) the ten titles - Super Mario Bros, Metroid, Donkey Kong Jr,The Legend of Zelda and its side-scrolling sequel, Balloon Fight, Wrecking Crew, Mario & Yoshi, Ice Climber and NES Open Tournament Golf - are available now.
It's a roundabout way to get them. Go to the eShop and scroll through to Settings, then select "Titles You've Downloaded". The new selection will appear there with the option to re-download, though you'll have to manually select and download each in turn.