The discovery of a footprint is providing a glimmer of hope before the search for a preschooler on an outback homestead becomes a recovery operation.

Four-year-old August, known as Gus, disappeared from his family’s sheep station in the remote South Australian mid-north on Saturday afternoon.

Alone in searing temperatures and without food or water, authorities’ best-case scenario on Wednesday was that Gus had crawled into shelter and was waiting to be rescued from the property near Yunta, about 300km north of Adelaide.

In a significant development, a footprint was found on Tuesday night, buoying searchers.

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“We had a little bit of a breakthrough yesterday where we found a footprint about 500 metres away from the property,” Supt Mark Syrus told ABC Radio

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