I upgraded my ReadyNAS 10200 from 6.2.4 to release 6.4.0 and I noticed that I lost the time servers during the upgrade. When I checked the box and entered the time servers again, then hit save, the time updated. But if I open the Set Time page to check the settings, the box automatically unchecks and the time servers are all removed. I can re-enter and it works fine, but unlike earlier releases, you cannot just check the Set Time page without having to re-enter the NTP time server information.
On another note, I see the Log-Off icon is missing from release 6.4.0 - At least I can't find it.
I have also noticed the changes that you mentioned in your post. With regard to the time setting, if the option is ticked without the time servers, it will automatically look for the default NETGEAR time servers. If you are using a different one, there's no other way but to re-enter it. The logout button has been been unavailable since the 6.4 beta has been available several months ago. You can check this post for more information.
