It is a matter of fine tuning
Let your Script breathe... Let a script breathe? Come on. A script isn't human (not before your shoot it) so how can it breathe?
Think of it as a child, your child. You must have at least nine months of pregnancy to have a child. There is no instant child. The same is with a script. There is no time limit when you write it unless you are professional and someone hires you to write it. For a freelance writer it can take months or years to have one ready and even then it is not finished until the film is shot and edited.