There are a number of rights and privileges that a website administrator has - but the real question is what do the leaders want you to do?
It's possible that they don't want you doing some things, but do want you to handle others. I'd like to believe that people are called to fill a need, not because there's a match between a vacancy and a available body. While the handbooks prescribe certain things be done a certain way, there's also a lot of flexibility to allow the leaders to organize the details as they see fit. So I don't think there's a standard answer of what Website Administrators are expected to do - because that depends on how the leaders want to mange some of he details.
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