Which rail a message goes out on, for a line that carries more than one.
"sms" names the SMS rail: the default on a WhatsApp line without calls, and the
same as omitting it on a standard number. An iMessage line offers no forced-SMS
send, so the API refuses "sms" there with 400.
Which rail a message goes out on, for a line that carries more than one.
"sms"names the SMS rail: the default on a WhatsApp line without calls, and the same as omitting it on a standard number. An iMessage line offers no forced-SMS send, so the API refuses"sms"there with400.