Change screenshots of app after submission
Even more recently (who knows when...) apparently you can change screenshots again while the app is waiting for review.
More recently (2015 or earlier), you cannot change screenshots even while your app is "waiting for review."
You are not allowed to change them after the app has been approved so be quick. See this news release by Apple:
This move is thought to be a way to deter spammers from posting a fake app and then changing the screenshot to mimic an existing popular app.
Update after talking to Apple:
On 2015-08-18 @ 12:30pm EST, the answer is still NO -- but there is hope.
I spoke with Apple on Monday, 2015-08-17 and after investigating the issue, they explained that iTunes Connect Screenshot uploading has a temporary error due to ongoing updates to iTunes Connect as aforementioned at WWDC. They are now aware of the issue and their engineers will restore the legacy functionality allowing us upload new images while Waiting For Review, as soon as possible. Meanwhile, if one needs to modify screenshots, simple "Remove this version from review", change the screens, then re-click "Submit For Review".
I hope this helps.
:-)
On 2015-08-16 @ 2:48am EST, the answer is NO.
I can not edit, add, or remove screen shots in either Safari, Chrome or Firefox at time for status "Waiting For Review". I cannot do it before editing anything else - like the title or keywords, which ARE editable - nor can I do it after editing anything else.
I have read all of the guidelines provided in the links above in full. At a certain point, it becomes circular linking regarding editing metadata and app statuses. Yes, screens are locked when the app is not editable, but all indications are that Waiting For Review is an editable status. There is nothing stating this is not the case. Heck, at the top of the App's screen is blatantly states: "(i) You can edit all information while your version is waiting for review. To submit a new build, you must remove this version from review."
However, one CAN NOT do it. This is a real blow as one will not realize this until it is too late and one is reading these posts - and now one realizes that one has lost the time and must reject and re-queue. Either that, or go to market with inferior metadata screens.
I will call the contact number in the morning at 7am PST. If anything changes, I will update this post. If not updated, one can assume this is the final status as of this time.
*** Sadly: If you need to change your meta screens, and you cannot do it, stop hoping, stop reading, I am sorry to say: You cannot do it. Cancel the submission, change the version number, change the screens and resubmit the sooner, the better.
:-(