The software version of this update is R805FXXU1CRKA/R815FXXU1CRKA for 42 and 46mm respectively and the size of the update is 38.63MB. According to IoTGadgets, this update is currently being rolled out in Australia/New Zealand.
You can check the update manually via the Samsung Wearable app while connected to the supported smartphone. For that, just go to Settings > About Watch > Update Now > Download updates manually.
Improved Samsung Health experience
Improved GPS accuracy and connection
Improved battery efficiency
Added Dual Clock Watch face
Removed menu - Use Gear without phone connection