I applied online. The process took 5 weeks. I interviewed at bp (Sunbury, England) in Oct 2013
Interview
So it started off with the initial application which just consisted off personal details, your education and a CV. The standard stuff. I then got invited to the main application stage which consisted of competency questions as well as questions about their company values. From that I was offered a 30 minute competency phone interview and after that I was invited to a technical interview that lasted an hour an a half; this is where I was declined to advance.