Spot on Zig,
There is so much variation even within the SAME clutch of many carpets that without information from the breeder you'll never be certain.
I certainly see what I think are IJ characteristics there, but here in the US so many things have been crossed and bred it's never a sure bet.
Here is an example. These are the parents of my snake.
The breeder found/rescued the female (background) from the side of the road. She is 9.5-10 feet long now. The male is around 8 feet.
Mum on a clutch.
Pops out for a picture.
At purchase, all I wanted was a carpet python and the price was decent so I was not overly upset not knowing what the mix was. They were sold as coastal carpets.
This is what I have from that clutch. She is 6 feet long, maybe 6' 2" and pretty thin. She will be 3 years old this spring. I see very little resemblance so far but she is young still.
I occasionally ask others what they think.
I usually get a mixed bag of guesses.
Jungle, coastal x jungle, coastal x jungle x diamond (diamond based on 1 parent's appearance), coastal x jungle x Darwin, and yesterday jag sibling x was tossed in. I'll never breed her so I don't care.
My point??
Nobody knows.
My next point?
If you like your snake, and it is very pretty, don't get too wrapped up in the "What is it?" part.
ALL morelia are semi arboreal, most in the carpet/bredli group are fairly busy and not shy.
That said I THINK the others who've said IJ are on track as there are characteristics that the Ssp has that show up in your snake.
Enjoy.
Edit: OP, I agree that in photos they can come out more yellow. My girl looks more yellow than she is a lot of the time.