to walk a hunter trial course on the day? If the competition starts at 10.30, and your class is the second to go, what time would you arrive at, without making yourself rush?
Its difficult if you havent been given specific times but agree with arriving between 10 - 10:30. Get yourself familiar with the layout and then toddle off to walk the course.
Depends how long the course is and how far away from the lorry park but at BE events I always put aside 1/2-3/4 hour to do my course walk as they are quite often a fair way from the lorries and theres nothing worse than rushing... great when you're competing on your own with one horse but not always practical ! I'd say set aside an hour in your mind and if you find yourself doing it in 15minutes with loads of spare time then at least you won't be rushing and faffing about before your warm up !