I applied online. The process took 6 weeks. I interviewed at G4S (Derby, England) in Jun 2017
Interview
Wouldn't call it an interview. Completed a few bits of paperwork and filled in an English assessment took photos of documents and that was it. After interview it took a few weeks for vetting forms to get sorted. Then didn't hear anything for 2 weeks or so before I chased it up and no one knew who was dealing with my application or vetting forms.