Bubbles121
ULTIMATE Member
As I said prior. None of this seems to apply to Vodafone as long as the device isn't connected to an actual foreign network. I didn't think it'd work after letting it connect to AT&T, but taking it off network and going on WiFi, it connected back to WiFi calling again and calls+texts were standard UK rate. (It was PAYG with no extra credit. Only a bundle).Generally you’re gonna hit 4 roadblocks with WiFi Calls Abroad:
1. Your sim will store and provide the network with the last connected network PLMN. If this is not your home provider they can use this to determine that you are not within the country and reject your request for service.
2. Geo IP restrictions can apply and the service provider can reject your request if it is not coming from an IP range registered to the UK.
3. Providers can set a maximum latency for the connection, and can prevent connections over a certain latency. This is generally done to preserve service quality, but can also be seen as a measure to prevent the use of VPNs abroad to get WiFi calling working.
4. Providers are able to determine a default set of settings per device, and on both android and iOS can determine their ability to even attempt WiFi calling while in a roaming state. This can be bypassed for android devices with custom ROMs etc and your own carrier configs, but would be impossible to bypass for an iPhone.
The only real way you can attempt to preserve this functionality is to determine which of the above scenarios apply to you and your network and take mitigation steps such as locking yourself to the home network before roaming and getting yourself a travel router with VPN functionality.
Keep in mind ANY slip up could result in the device pinging a network and being left unable to then connect back to WiFi calling for the rest of the trip.
The latency perhaps does matter as it wouldn't work on the plane, but that's only an extreme case. On the ground in the US on their broadband and WiFi networks I could always get WiFi calling to work with VF. Nothing on Three or EE though as expected.























