Usually blinking cyan is after getting connection to the carrier (WiFi or cellular - blinking green).
First contacting the Particle Cloud servers (same speed as green blink but cyan) and then during handshake with the Cloud (rapid cyan blinking) ending in an established connection (cyan breathing).
Is this what you see or do you see any other cyan blinking?
Could you provide a video of what you see (including the phase leading up to it)?