Why would the runway lengths at Jandakot be a problem?
Because of the 1.67 factor they will need to apply to the book landing distance figures.
What are they saying for the landing distance?
If you start with the greatest LDA at YPJT, which is 1,274 m for runway 06L, and work backwards through the 1.67 factor, you get a theoretical book figure of 762 metres.
So, to land legally at YPJT the book figure for the landing distance required will need to show 762 metres or less. That is getting a bit tight.