5G to VoLTE or 3G

[Techhead]

I’m trying to work out if I have a problem or if my iPhone 12  is doing what it should. 

I was under the impression that when I am in a 5G area and a call comes in then my phone should drop down to 4G and use VoLTE for the call.  (EE doesn’t have 5G Standalone/VoNR)

However what actually happens is that my phone drops to 3G for the call. 

This would obviously be concerning as 3G is being switched off soon. It might also explain why sometimes when I dial it take 30to45 seconds to connect. 

So I wanted to check whether I’ve misunderstood what should be happening (and my phone will then drop to VoLTE when 3G is turned off) 

Notes: Carrier settings 54.0. Tested in multiple areas with good or excellent 5G 4G and 3G. Phone is dual sim and a Vodafone SIM switches to VoLTE. 

[BPW]

It would not be a concern because your phone would then drop to 2G for calling instead! and 2G will run alongside the other network technologies for some time yet.  you can't manually select 2G on a recent iPhone but your phone should switch automatically to 2G if no other network is available.