Configuration assistance sought to assist with enabling VoLTE support for Nexus 6 device, understood that some network settings may require source code / XML adjustment and compiling back into image that can be tested in Nexus 6 device to be tested in private band7 LTE network. In depth understanding of how the source XML carrier files are configured required.
Minor edit as I think its suitable for some one that understand how source XML carrier, DB files and android framework are configured - suspect what's needed is to download from Android Open Source Project (AOSP) the source code and locate the various settings that control the Volte/LTE configuration. Success is enabling device to attach, register to LTE network and make VoLTE call. Should be quick and easy ?