You can find the LED status guide for Reach Module here.
Reach has three LEDs which are used as status indicators for three different parts of the system.
This LED lights up when Reach is connected to a power source.
During boot, Reach enters a network scan state in which it will try to connect to any known Wi-Fi networks it can find. This might result in connecting to a previously added network or creating its own hotspot.
Stat LED is used to display ReachView 3 status.