I was sent the following information from the organisers and thought I'd share it with you, in case it is of use:
The competitions have large entries so the slot for rounders, of 10.30 – 3.30, is based on the number of teams. The competition will be going on for all of this time although obviously your school will not be necessarily competing at all times, there will be breaks during the day.
The organisers have tried to schedule it so teams play as many games as possible so there will be plenty of matches for parents to watch.
The Basildon Sporting Village is based at Gloucester Park, most people know the tractor plant in Basildon, (you drive past this on the right) and the Sporting Village is about a mile further up on the left (almost opposite Festival Leisure Park).
I hope that this information is useful.