To be honest, I think it makes very little difference which timezone a moderator lives in. I mean, just because someone lives in the UK (for examples sake) doesn't mean they will be online at any particular time. The mods will still only be able to visit when they get chance in the day, and that isn't always so easy to predict. Perhaps some of them are like me and keep very weird hours. For example, I live in the UK, but I'm most active on the net usually between 22:00 and 02:00, which I believe is peak visiting time for most of the US users.
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