After 8.4 upgrade, "add to home screen" apps do not fully load

First hold the sleep/wake and home button until the apple logo appears.

Even though it's weird I had the same issue and saw that if you change the language on the iPad and then change it back the icons stay and it worked for me.

Try opening the links and then closing them again. You may also find some other tips on this post: Lost bookmarked to homepage icons ios 8

You are welcome. I had the same issue and changing the language also fixed my iPad my icons.

Unfortunately, I don't have any other ideas. I would submit that to Apple feedback: http://www.apple.com/feedback/