Changes to a award flight one year from now?

I am about to book a award for with the outbound in August end and the return I want in August first week 2014. As of now I can only see awards till June end 2014.

How long is a award ticket valid for? 1 Year?

So say if I book return for June 14 now and can I then call up a few months down the line and shift to a August middle return ticket? A normal paid ticket is valid for a year so this should be possible right?

Also is a RTW award allowed? Say if I go from Asia to LAX via Europe but then come back via west coast.