The Pottermore site was announced last year, with a scheduled launch in October. But a statement posted on the site this week says testing was extended after feedback from early users made it "clear that our original platform wouldn't be suitable when millions more users came on to the site."
The site is supposed to offer e-book editions of the seven Potter novels, but Rowling spokesman Mark Hutchinson said Thursday that the sale date for e-books had not been confirmed.
Rowling for years had resisted making her work available in digital form.
