iOS Updates on iPhone 6

I'm using the iPhone 6 and there is the new iOS 8.4 update. But from past experiences, there would be a badge app icon on the Settings app, and after pressing General there will be a grey '1' on Software Update. But it does not now, and I have to manually go to Settings and General to Software Update to see the 8.4 update page without prior notice from my iPhone. Is it safe to press 'Download and Install', or will any content be missed? Please give advises or tips if possible.