I think that’s some sort of forecast. Even this page at the same website shows 924mb as the pressure at quad-zulu
https://www.tropicaltidbits.com/storminfo/
Yes it is a model “Projection” and it is almost 42 hours from now. Of course it is subject to change. Its just a prediction based on a mathematical model(a very complex formula). Current weather information is input, and the model runs. Unfortunately as we have seen again and again- It is subject to some error. Usually it gets closer to nailing the actual path the closer it gets to real time.