ObsidianZedTo clarify, my carrier is AT&T in the U.S., so not even the same carrier or country as OP.
I created an account to post a similar discussion. I know Asus is "working with providers" to enable support for VoLTE, but it would at least show some thoughtfulness towards their consumers if they showed what all providers they were working with and in what countries.
If they're working on it, fine. I'll be patient. But if I know for a fact that they are not even attempting to support my provider in my country, then I'll start shopping for phones.
I don't even care to receive Android 11 so long as I can still make calls from my phone. But if it won't be supported BEFORE 3g voice services are deprecated, then my "ROG Phone 2 Ultimate Edition" was not at ALL worth the cost.
It's obviously a long shot either way, but I might be willing to stick with Asus if they were to have a special trade-in offer only if your phone will no longer support VoLTE.
ObsidianZedAT&T won't allow VOLTE for any device that isn't carrier locked through them. I have red Pocket gsma which is a mvno on AT&T towers (hence the "A" in gsma.) and I don't have it and probably never will given how shiesty AT&T business practices are. But hey at least they've nearly tripled 4G data speeds to make up for their garbage 5G
To clarify, my carrier is AT&T in the U.S., so not even the same carrier or country as OP.