Experience as on 30 July:
This is complicated and needs to be explained in phases.
Initial Phase : When the telco first started VoLTE
1. Auto Activated on some compatible devices or
2. Customer needs to send a message for activation.
After activation Call drops became the new normal and voice is patchy too. VoLTE sign used to appear and vanish and this used to happen most of the times.
Ok understood, they are still fixing things.
Next Phase : VoLTE got fine tuned
Things got better, call drops reduced. VoLTE is stable, but still needs tuning. It's not a HD experience but okay, not bad. Upon Activation message, VoLTE gets provisioned based on device compatibility.
Now : Hanging between the TWO brands and unified provisioning
Which ever compatible device you insert the SIM, VoLTE remains active. Activation is smooth and see no hassles with it(via SMS/USSD). Though never experienced a true HD voice (the voice codec factors) but once VoLTE is activated it works on compatible devices.
In some circles, brand V launched and provisioned VoLTE and in some circles brand I launched and provisioned VoLTE.
For now this scenario can be best described on venn diagram as intersect, Union, Minus/Except, joins between brands, circles, devices.
The worst VoLTE experience is from VoId. Even BSNL VoLTE experience is much better, imho. I have Idea number in TN. TN is one of such states where both Voda and Idea have separate VoLTE services. Even though Idea is a Joker network in TN, I bought it to use in MP-CG circle, where Idea is good and Voda is a Joker network.
I am using it in my Moto 1 Power and VoLTE works. But the VoLTE experience is NOT great. Even Airtel 2G call clarity is much better than Idea VoLTE. Further VoId activated roaming VoLTE very very late, till that time calls fallback to 3G while roaming in MP-CG. Call clarity was OK. I was expecting much better call clarity after start of VoLTE roaming. But frankly speaking, Idea's 3G voice calls are much better than their VoLTE call clarity, when roaming VoLTE was enabled. Insult to the injury was VoLTE roaming NOT working in MH circle (though works in MP-CG, KA, AP), where Idea is NUMBER 1 operator, even till now. I mean - come on, MH is a star circle for Idea, but Idea customers are NOT allowed to use VoLTE there while roaming. Since their VoLTE clarity is NOT great, its OK for me. But the fallback to 3G is a thing of worry as well, eg:- download speed drops drastically, calls get missed sometime. When talking about VoLTE coverage, again its a pain. While travelling in train, VoLTE vanishes in non-urban areas. This is as per my experience by Feb2020 first week, not sure the situation has changed now or not.
So VoLTE of VoId is a total disaster, in my experience. Wrt VoLTE call coverage,
Jio >> Airtel >>> VoId >>>> BSNL.
But wrt VoLTE call clarity,
Airtel > Jio >>> BSNL > VoId.
Dear VIL, whether you survive or not is a different question.
Please rollout VoLTE (or VoWiFi) on immediate basis (on the other brand) in circles where at least one of your brands has VoLTE active.
For a software provisioning, hope you don't take the brand for a beating.
At least in my case, I stopped using voice on my number and have been forwarding calls to other number just to use voice services.
Having no 3G, voice fallback on 2G is pathetic. It is hardly audible or clear.