State of MMS on Librem 5

Hardware Librem 5
159

My situation:

Network: T-Mobile
Network Mode: 3G, 4G (Preferred)
APN: fast.t-mobile.com
MMSC: http://mms.msg.eng.t-mobile.com/mms/wapenc
(APN/MMSC settings match in both the Mobile Settings and in the Chatty preferences)
Using Chatty 0.7.0.rc5
Using Byzantium: Linux pureos 6.1.0-1-librem5

As of today:

  1. I can receive images and text from others in a group MMS but if I reply with text only, my reply is NOT received.
  2. Images that I send individually or to a group are NOT received.
  3. SMS messages I send to myself are NOT received.
  4. SMS messages I send to a single individual ARE received.

Do I need a new carrier?
Do these SMS/MMS messaging functions all work on AweSIM?