Did I see fomalhaut or achernar?

[Jayla]

After a drive back from a dark site doing some AP, I took one last look at the skies from the garden before calling it a night.

Clouds had rolled in, but I could see a bright star close to the horizon in a southern direction. I was intrigued because it was flicking between a turquoise, white, and red colour.

I grabbed the bins (40x25), it was definitely a star and not an aircraft (single point of light, small like a star, not moving).

Having checked stellarium, its most likely to be fomalhaut or achernar, unfortunately as cloud covered most of the sky and LP leaking up from the horizon, I couldn't see any other stars to use as a reference.

5:15 am, Melbourne time

About 10-20 degrees up from the horizon

Southern direction, about 150 degrees

Having checked the wikipedia entries, both are listed as blue stars, which one did I see?!