As another example of how the sun doesn't set for summer, here is a photo of the sun at 11pm near the summer solstice (middle of summer).

While the sun may look like it is going to set, it isn't as it will just skirt the horizon.

Below is another map that shows the Aurora Australis's voyage track for the 1999/2000 season.

I spent nearly 2 weeks on the Aurora travelling between Hobart and Mawson on voyage 2 (V2), marked as the dashed orange line.