AT&T and their MVNO resellers are saying my phone with this ROM will be useless after February 2022, but they don't really know because it's an international phone. I've been scrambling to finally get a proper AT&T CSC, so that voLTE and HD Voice might work. I had been relying on 3G calling all this time, but that will be phased out. I tried Selection CSC 2.0.0 Final for Oreo, but it makes my phone unstable (IMS crashes repeatedly).
Does anyone know how to get a proper AT&T CSC for this device, and this ROM? Others have tried, but a few seem to have made it work... without providing documentation. It seems like it's more than just an XML CSC file, because the AT&T CSC comes with all sorts of ".jar" files and such.
I might have to downgrade to an Oreo ROM just to be able to use this phone! I love Deluxe ROM so much!