I decided to change the firmware using the Arduino IDE. This proved to be very easy to do once I switched the board to UART mode.
I followed the instructions given on https://learn.adafruit.com/adafruit-huzzah-esp8266-breakout/using-arduino-ide to add the board to Arduino using board manager.
I tested one of the ESP8266 examples to create an Access Point. It uploaded the code first time without error and I was able to access the webpage. It was quick.
However, I now wanted to use serial interface through the Arduino IDE to debug code changes using the Arduino Serial Monitor. I was then looking to reset the ESP8266 module to trigger the UART comms but cannot find a way to do it.
Is there a way to reset the module, or is it the case that I now have to change the board mode back to FLASH mode to get the serial comms working again.