In brief
Developers must submit a new app version for App Store review to change its description or release notes. Only the privacy policy link can still be edited freely, so even minor text corrections require a new release.
Apple has quietly changed the functionality of the iTunes Connect interface. Developers can no longer freely change an App's description, update its release notes or add other text. Developers can now change an app's description only after they have created a new version of the app, which must then be submitted to the App Store for review.
Previously, developers could change the information presented in their App Store listings and edit the release notes under “What's New.” Now, the only field they can change is the privacy policy link. This means that developers must create a new app version, change the app description, resubmit it to the App Store and wait for the review to be completed. It also means that if developers find a typo in an app's description, they have to wait until they release a new version to correct it.
It is currently unclear why Apple has stopped developers from changing app descriptions. In addition to app descriptions, developers can no longer change app screenshots or app names. Although app updates now take only 24 hours to review, this restriction on editing app descriptions will still cause difficulties for developers: simply changing a few words of promotional copy requires them to submit a new version.