I’ve read that until means:
up to the point in time or the event mentioned
Now the question is, which of the following is correct, while I mean to say that ‘You must leave so that things can be good here.’
1. Things will not be good until you are here. 2. Things will not be good as long as you are here.
I feel the second one is correct. The first sentence seems to mean: to make things good you should come here. i.e. that person is not here.