Hey
We are yet to announce all details for the LTE modem, it should be out in few days. But WiFi calling is not supported by the modem. It is more of a modem firmware thing, but it is quite complicated in my understanding, and requires close integration between the modem and WiFi which in case of the Comet are discrete components. Quectel / Mediatek SoCs pull it off because WiFi and Modem are sitting inside the SoCs.
Shoaib