Got this email this morning after uploading my latest build to test flight:
"We identified one or more issues with a recent delivery for your app. Your delivery was successful, but you may wish to correct the following issues in your next delivery:
ITMS-90809: Deprecated API Usage - Apple will stop accepting submissions of apps that use UIWebView APIs . See https://developer.apple.com/documentation/uikit/uiwebview for more information."