It is actually an iOS issue and not PhoneGap Build issue. It has happened before with another iPad model.
I have been told that using WKWebview solves this issue. You change your webview using this plugin:
I have not tested it fully, so your milage may vary.
I gave the cordova-plugin-wkwebview-engine plugin a try, but it broke the cordova-plugin-splashscreen plugin.
Actually I was wrong. Switching to cli-6.X broke splashsceen. Both splashscreen and wkwebview are working with cli-5.4.1.
Anyone know why cli-6.X would break a working splash screen config?