The abstract is an important summary device at all stages of your candidature. It helps orient others quickly with what you are doing, and is important for the documents accompanying your milestone review presentations. When it is time to be examined, the abstract is often used to contact potential examiners to see if they are interested in engaging with your research in that way.
An abstract evolves into an increasingly concise statement as you progress through candidature.
Early in candidature, the abstract conveys how you intend to research through particular activities of creative practice, what you hope to explore by doing this, and with what objectives in mind. As you progress through your candidature, the abstract can be refined to summarise how the research is gaining clarity and focus through your increasing understanding of what and how you are practicing as research.
In the later phase of candidature, the abstract needs to summarise the focus of the research, how the research was undertaken, and the contribution the research makes to the knowledge of a field or community of practice as you define it, and potentially to yourself as practitioner.
Keeping a list of past abstracts as they evolve and develop can be very revealing to look back upon as the research progresses.