Editing Screenshots iTunes Connect for Approved App

While previously Apple didn't allow editing screenshots without a new binary, as of Sept 2010 they say this: Screenshots are now an unlocked metadata attribute and can be updated at any time

Ok, that's good, but when I go into iTunes connect and click the Edit link for my screenshots, I see options to re-arrange or delete screenshots, but no upload box, to put in a new one.

Do I have to delete a screenshot before the upload box will appear? That's my guess here, but I don't feel like experimenting. So much for in开发者_如何学Ctuitive interfaces.

Yes, if you have 5 images, you have to delete one first. It's the same when you upload your app and add screenshots for the first time.