An update has been rolled out that resolves this issue and keywords have been updating normally for the last hour or so. We'll be keeping an eye on updates for the next few hours, but everything should be working normally now.
Posted May 23, 2020 - 13:13 EDT
We've identified the source of the issue and are in the process of rolling out an update
Posted May 23, 2020 - 12:23 EDT
We're investigating reports of keyword ranks from the App Store not updating on schedule