Change Photon SSID

I see that I can set the prefix and suffix manually right now with:

System.set(SYSTEM_CONFIG_SOFTAP_PREFIX, "hello");
System.set(SYSTEM_CONFIG_SOFTAP_SUFFIX, "hello");

However I was wondering how the factory suffix from the Photon was generated? Is this a part of the DeviceID (which is a lot more characters) that I can get with System.deviceID();?

I’d like to use mDNS / Bonjour to discover my Photon and was thinking to use the preconfigured suffix. However there is no System.get command in the firmware I think, since it seems commented out in the code: https://github.com/spark/firmware/blob/27dec24644c58935af728b00adb742f7d18a5b86/user/tests/wiring/api/system.cpp