Not to much longer I would say 5days max but every guppy is different start keeping a log how how may fry and how many days. This will help you know when the next drop will be
It looks like she is ready to have them soon. A good way to tell if they are ready is if their gravid spot is square shaped. Here is how you tell: look at the her dark spot with the tail facing you. the spot will be either rounded or square. Square looks like this: \_/ and rounded is like this: (_)