If you give an idea of the different times she is considering going people here can give you a general idea of what the crowds and hours will be, and there are certain predictable ride closures for holiday overlays or the removal of overlays, but as the above poster stated, Disneyland doesn't post schedules or announce closures very far in advance.
As far as tips and tricks go, there are about a hundred sites you could go to, or you can give more info here (is she traveling with little kids, how long is she staying, etc.) and get tips and tricks from people here.
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