couple of observations which may or may not turn out to be relevant
This was reported with systems running powerd and repowerd so seemingly not an issue at that level.
Both logs show that at some point prior to the undelivered message the modem connection was lost and reconnected. I was looking for some evidence that the modem stopped being a wakeup source. Grep for "active wakeup source" shows radio-interface when the last two texts work and not when the third to last did not. Nothing solid here though.
couple of observations which may or may not turn out to be relevant
This was reported with systems running powerd and repowerd so seemingly not an issue at that level.
Both logs show that at some point prior to the undelivered message the modem connection was lost and reconnected. I was looking for some evidence that the modem stopped being a wakeup source. Grep for "active wakeup source" shows radio-interface when the last two texts work and not when the third to last did not. Nothing solid here though.