When we originally added Assessment Goal functionality a few months ago, the one issue was that a trainer wasn't able to set a goal date. This made it difficult to edit goal values or change the value if you made a mistake.
That said, we thought it would be easiest to first add a drop-down picker on the Edit Data button.
And then give you can access to every single goal value so that you can either revise your client's goal or delete it completely from the system.
FYI - This also means you can set a goal for a future date...