Upvote:4
As a holder of a British passport, you will need either a Transit Visa or an electronic visa (eVisitor).
Your eight hours five minute transit time causes to fall afoul of the rules allowing transit without visa:
Travellers must:
enter Australia by aircraft
hold a confirmed onward booking to leave Australia to travel to a third country on the same or another aircraft within 8 hours of arrival in Australia
hold documentation necessary to enter the country of destination and
not need to leave the airport transit lounge except to continue their journey.