I got an update today on my 1520 with Preview. It shut down the phone and everything. Is this the number of os for cyan?
Sent from my Lumia 1520 using Tapatalk
Cyan is a firmware update, not so much for OS (same 8.1). But your firmware version matches mine. So, it looks like a Cyan update now pushed out to DP users.
To see what firmware you have, open extras+info app and it will state which firmware you have, Black or Cyan.