You are invited to the main office in Stratford, where you along with anyone else with an interview are brought into a room where you must complete two tests.
Both the tests are incredibly easy, the content is simple: Basic math questions, Comprehension a child could complete, rewriting paragraphs.
You will then be asked some questions.
After completing the basic tests your interviewer will speak to you briefly.
Then for me personally I was offered the position immediately.