I believe usually the network would set the time, but there won't be one in this case. I've had success with an Emteria build that used the same GPS HAL to set the time, but that was a much earlier version of Android - using the GPSTest App you can see the time just fine, just setting won't work. Could be the permissions as I think it would need root for this operation.I haven't looked into the time_sync on the GPS HAL. Not sure if related but does the Android itself sync time using it in a car? You would need to have a network connection or an external RTC module for this.
Nothing has really changed regarding 64-bit since it was last discussed (https://forum.xda-developers.com/t/...raspberry-pi-4-b.4212945/page-2#post-84352695).
Vulkan drivers are not something that you can just simply install. The support for it needs to be implemented on the OS. Currently mainline Broadcom Mesa Vulkan driver doesn't support Android (it's not built as an Android HAL unlike for some other platforms). android-rpi has initial support for vulkan (https://groups.google.com/g/android-rpi/c/FCC0h5vlgl0) but I'm not sure what is the exact status with it. android-rpi uses entirely different Android graphics HALs than this build but probably worth checking out if you need vulkan.
Seems easier to shell out for an RTC module than fight my way through the code, as I can't reproduce these builds.
Once again, thanks for the all effort.