ESP8266 firmware update using espruino pico

With 'Does testing the firmware version work with the ESP8266 as it is normally?', I mean does running this command work:

function test(serial, baud, pins) {
  serial.removeAllListeners();
  var l="";
  serial.on('data', function(d) {l+=d});
  serial.setup(baud, pins);
  serial.write("AT+GMR\r\n");
  setTimeout(function(){console.log(JSON.s­tringify(l));},1000);
}
test(Serial2, 9600, { rx: A3, tx : A2 });
// wait 1 sec

And then:

test(Serial2, 115200, { rx: A3, tx : A2 });

The revision of esptool shouldn't matter - but I have to admit I haven't tried with the absolute latest version (although I don't think there are major changes).