TP has posted park hours up to Oct 3rd. the disney site is only up to Sept 22. Are TP's hours accurate. Do they know something that they can post the hours.
TP uses historical data to determine hours. If the hours they post are beyond the dates available on the Disney site, they are only making an educated guess at the hours. They don't have any special access or advanced knowledge of the hours. They update the hours once Disney updates their hours. They are generally pretty accurate, though!
One extra note, there is a difference between the dates available for seeing park hours between the Disney website and the MDE app. While the site only has hours available through September 22nd, the app has the hours available until October 2nd. Also, you'll note that the TP calendar prefaces dates after October 2nd with "est" for estimated.
Let me add that the hours now shown on the Disneyworld.com website and MDE app are not final. Disney can and sometimes does change the hours between the time they first appear on the calendar and your park day. That much more often involves increasing the park hours rather than shortening them. Since 2020 (and 2020 was unusual for obvious reasons), I believe they have only shortened hours due to approaching hurricanes and tropical storms.