A setting to let users exclude T-Mobile WiFi calling IPs

[ignoramous]

A user writes,

I have tried setting Rethink's network to "Choose IP version: Auto," as I'd read something about T-Mobile's network dealing only with IP6, which I generally otherwise disable. However, the problem persists: I cannot activate Wi-Fi calling. In fact, no other configuration of the Rethink app's settings allows me to activate Wi-Fi calling. The only way I can activate Wi-Fi calling is to completely turn off the Rethink VPN in my Android settings, then activate Wi-Fi calling, and then turn Rethink back on. It appears that Wi-Fi calling then remains activated, but I'm not actually sure if my phone is truly using Wi-Fi calling to make calls in that situation.

Exclude T-Mobile IPs: https://github.com/M66B/NetGuard/blob/feef4c7b3beca3ed4b44250b580c637554a9d44f/app/src/main/java/eu/faircode/netguard/ServiceSinkhole.java#L1352-L1370

            // T-Mobile Wi-Fi calling
            if (config.mcc == 310 && (config.mnc == 160 ||
                    config.mnc == 200 ||
                    config.mnc == 210 ||
                    config.mnc == 220 ||
                    config.mnc == 230 ||
                    config.mnc == 240 ||
                    config.mnc == 250 ||
                    config.mnc == 260 ||
                    config.mnc == 270 ||
                    config.mnc == 310 ||
                    config.mnc == 490 ||
                    config.mnc == 660 ||
                    config.mnc == 800)) {
                listExclude.add(new IPUtil.CIDR("66.94.2.0", 24));
                listExclude.add(new IPUtil.CIDR("66.94.6.0", 23));
                listExclude.add(new IPUtil.CIDR("66.94.8.0", 22));
                listExclude.add(new IPUtil.CIDR("208.54.0.0", 16));
            }