Not all Sierra modems support it, but those which do reply like this:
AT+CPINC=?
OK
AT+CPINC?
+CPINC: 3,3,10,10
Not all Sierra modems support it, but those which do reply like this:
AT+CPINC=?
OK
AT+CPINC?
+CPINC: 3,3,10,10