From Halopedia, the Halo wiki
During an unknown battle in October 2552 shortly after landing, ODST Sarah Palmer reported in to Bossman. However, she quickly cut him off as Covenant reinforcements arrived in the area and she had to protect Admiral Kovalic. Later after securing the admiral and escorting him out of the area in an M12 Light Reconnaissance Vehicle, she reported into Bossman that she found the admiral. He interrupted her sounding surprised the admiral was alive and informed her that his evac ride was waiting just south of her position and sent her the coordinates.
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