Hast in hand refers to something that has already been started or is currently being worked on. If you need to find an alternative way to express this concept, there are several synonyms available to use. For instance, you could say you have something underway, in progress, in motion, or in the works. Alternatively, you could say you are currently handling something, managing it, taking care of it, or dealing with it. Another option to consider is to say that you have something under control, are overseeing it, or are already engaged in its completion. Whether you choose to use one of these alternatives or not, the key is to convey the idea that progress is already being made.