I've opensourced a Lua script that has been tested with OpenWRT 23.05.5 Lua 5.1 packages and ZTE 5G CPE MC7010 router for sending SMS messages. There's also a Python 3.10+ script that works outside of OpenWRT.
This is useful in sending alerts etc. from OpenWRT behind a ZTE router.
Project is available at
Contributions are welcome!
-Lari