Telecom question: USSD 2G 3G

[Spikee]

Hello All,

I have a question regarding USSD and disappearing GSM networks.

So USSD works over the voice channel which would be GSM.
The problem is that several countries are phasing out of GSM and 2G (and thus the voice channels?).

So here are the questions:
- The USSD provider told me that if there is no 2G network the voice channel still exists, is that correct?
- If GSM/2G is phased out there are no voice channels left right ? thus USSD won't work anymore.

I'm not closely involved in the project. These are just some questions others have and I thought someone on this forum
probably has expertise in this. Getting confusing / contradicting answers from others.

Thanks