This convenience rollup package contains all the security and non-security fixes released since the release of Windows 7 SP1 that are suitable for general distribution, up through April 2016. Install this one update, and then you only need new updates released after April 2016. And since this update can be injected into Windows 7 SP1 media, it's fully supported to mount a Windows 7 SP1 image (WIM file), then inject this update into it.
This convenience update is completely optional; it doesn't have to be installed and won't even be offered via Windows Update - you can choose whether or not you want to use it. To apply this update, you must install the April 2015 servicing stack update for Windows 7 (KB3020369). We hope that you find this convenience rollup package useful. This same convenience rollup also applies to Windows Server 2008 R2.