PnP Sites Core - which Cumulative Update for OnPrem 15?

The https://github.com/OfficeDev/PnP-Sites-Core/blob/master/Assemblies/readme.md indicates "Current version: version deployed with the April 2015 CU: no separate redist (version 15.0.4711.1000)".  However, the https://github.com/OfficeDev/PnP-Sites-Core/tree/master/Assemblies/15 is showing what looks like March 2016 PU DLLs.  Can we safely targer April 2015 CU+ environments still with the Sept 2016 Sites Core libraries?