Does Librem 5 have VoLTE certification on Ting/T-Mobile?

[amarok]

See @Kyle_Rankin’s comment (he’s the CSO for Purism):

VoLTE support progress

For what it’s worth, I have been testing out VoLTE over T-Mobile networks by enabling the VoLTE mode on the Librem 5 modem (which is disabled by default right now). Once enabled, I can successfully receive calls over 4G. Unfortunately when I attempt to place calls, the carrier disconnects them, sometimes after the other side rings, sometimes before. When in this mode I have to go into modem settings and tell it to be 3G only and then I can place an outgoing call. This leads me to believe that …

@Euclid33

• Does the Librem 5’s hardware and software support VoLTE?
• Does the BM818-A1 modem that comes with Librem 5 have VoLTE certification with Ting/T-Mobile? (Ting says they don’t have the answer to that question, they implied that I should ask Purism–see their post from July 1, 2020 here: https://help.ting.com/hc/en-us/community/posts/360027576294-Librem-5-does-Ting-support-).

1. Hardware: Yes / Software: Yes, but not yet enabled in the UI, as they’re still working out the kinks.

2. Checking a Librem 5’s IMEI (BM818-A1) on the T-Mobile BYOD compatibility page indicates it’s approved. (This modem is commonly used in automobile systems.) T-Mobile doesn’t really have to specifically whitelist a phone (although the other networks do, I believe). As long as it’s compatible, they’ll activate it.

You might also want to check the following:

Will my existing SIM card work? What countries and networks will be supported?...

T-Mobile - United States - Wireless Frequency Bands and Device Compatibility

P.S. You could also check this map (zoom way down to your frequented areas, then click on the 4G icon at bottom right), to see the reported tower coverage in those areas, to see how the frequencies used by the L5 and by T-Mobile match up:

Explore Mobile Internet Coverage with nPerf Maps