Possible Sighting of a black cat

Hi. My name is Peter, and I believe that I might have seen something of interest today while walking along the Great Ocean Walk between Aire River and Castle Cove.
Whilst I am not sure I would describe what I saw as a "panther", I am in no doubt that it was a black cat, so I thought I would pass the information on in case it is of any value to your research.
I am visiting Apollo Bay for the week and have been on several walks. I can remember many years ago reading about sightings of "panther" like black cats in Victoria. I couldn't remember the areas, but after I saw what I saw today, I googled "Black cat Otways" and came up with your site.
I was walking along the track from the Aire River camping ground to Castle Cove. Total distance is 5.5 km. The walk took me 70 minutes one way, and I estimate the sighting was about 15 - 20 minutes in to the trip, so I estimate approximately 1.5 to 2KM from the Aire River camping ground. The time would have been approximately 1:50 PM Friday 8th May. I turned a corner in the track and saw a black cat running away from me. It had obviously heard me coming and disappeared very quickly. I estimate that I only saw it for about 2 seconds before it disappeared from view in to the bushes. I did not see it's head as it was facing the other way, but I got a good look at it's rear torso, hind quarters and tail.
I can't be sure exactly what size it was, as the sighting was so brief; but I can say my impression was that it was a bit bigger than a normal domestic cat. Domestic cats can vary in size of course so I would say it was the same size as a very large domestic cat. Not fat though. On the contrary it was very lean. It had short black hair and had quite a long tail, I estimate the tail was over 2 feet long. The tail was also short black hair.
When I googled "black cat" when I got home, I saw one report which described a "bushy" tail. You certainly could not have described the trail I saw as "bushy". It was long and slender with short black hair. As I said it was a bit hard to estimate the size because I saw it only briefly and can't be certain exactly how far it was away, but if I had to put a figure on it I would say the top of it's back at the hind quarters was about 18 inches to 2 feet off the ground. I don't have any idea what length it was because I didn't see the front of it at all as it was running away from me.
It could well be that I have just seen a large black cat turned feral; but I thought I would pass on the information in case it links in with other sightings in the area.
​Regards, Pete