The first paragraph in the linked support page states: We want to make sure you’re ready to use 4G Calling on our awesome 5G network
So 4G and WiFi calling is available on Virgin Media's 5G contracts which operate on Vodafone's network.
and in both sets of support device pages for 4G Calling and WiFi Calling the S8 is not listed.
I will also make you aware that a lot of networks do not support 4G Calling or WiFi Calling on devices not brought from the network and that may apply here too as it also stated on the support link All of these devices support 4G Calling if they are bought directly from us. If you are using a device that was bought from another network, or SIM free, we cannot guarantee that it will support our 4G Calling service.
I know personally that EE pretty much supplies all services it can to handsets but as it has been mentioned here already not all networks use the same methods to deliver these services and MVNO's (Mobile Virtual Network Operators) such as Virgin Media will not support features the host network (EE) do unless its part of the network leasing and sharing agreement of which both features above are not.
The WiFi Calling service from Virgin Mobile is a fairly new addition to the network made by Virgin themselves and separate from EE so probably isn't compatible with old generation devices.
4G calling may become available in the future however as Virgin move the rest of existing customers from EE to Vodafone's network but alas that is not due to happen until 2022, Only customers with 5G devices are getting these features as they are using Vodafone's network, they are crucial features for 5G to be able to receive calls, just like 3G is still crucial for Virgin's 4G because calls aren't transmitted using 4G
Yes, I've checked up and this is definitely for 5G Vodafone contracts. VoLTE has to work to make calls on 5G and to provide fallback to 4G as you move out of a 5G area. 5G calls will not fall back to standard 4G or 3G
I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more
Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks