Quoted from Magicman:No time zone setting. But if your game is connected to the internet, on boot up it will attempt to pull in the time from the internet, and if it's connected but you don't have IC feature enabled, it may pull in the wrong hour. Try this... set time in the utilities menu, power game off. Remove wi-fi dongle from MPU. Power game on. Without being able to connect to the internet, it should hold the correct time (but you won't be able to do updates via WiFi or use the IC feature. If by doing this it keeps the correct time you have 2 options: 1) set time manually and don't reinstall the WiFi dongle - you can still update code with a USB stick and it will keep the correct time
or, 2) If you want to keep the ability to do updates using WiFi, and also want the time to be correct, then you will need to enabled the IC feature and set up an IC account, because the game uses your IC profile information to determine your time zone.
I had the same problem, and upon boot-up my clock always reset to CST (I'm in the EST zone) so the clock always came up an hour off. I wanted to be able to download code updates via WiFi, but really didn't care for the IC experience. In the end, I relented and became assimilated to using IC, feeling a little forced into it though. But now I can still do WiFi updates and my clock always has the correct time. Hope this helps.
Thank you very much for the thorough explanation. It's exactly the answer I expected. I have not been using IC (not particularly interested in getting roped into a another online ecosystem), or WiFi for updates, as I find the USB stick drive method to be more reliable, so will probably just disconnect from WiFi and let the machine keep its own time.
Thanks again!