The intercity travel scheduling you see on the Route tab displays an average duration based on the available transportation options. If you expect your flight, drive, or train/bus trip to be longer or shorter than what the site suggests, you can change it on your calendar.
Navigate to the Calendar view on the Day by Day tab, click on the travel block, and specify your scheduled departure and arrival times. Your trip's intercity travel schedule will now match the bookings you've made or plan to make.