The Centrelink client will be required to disclose their new marital status,
and their entitlement will be re-calculated based on Joint Assets and Income Tests.
And just to be clear (since this is often the back-story to a question of this kind),
getting married to an Australian citizen (or to a P/R)
does not in itself create any right for the foreigner to stay in Australia.
What is the background to your question?