Dyson Helpdesk interview questions

Interview was with an outsourced company on behalf of Dyson. After interview I was introduced to interviewers manager and they handed in my application to Dyson. Everything was going well until they asked me when I could start. Advised them start of following week and they didn't seem happy with that (5 days away including weekend). Role was declined via letter - "Too IT experienced". Ongoing advertisement was changed to include backpackers. I believe they were looking for younger people to fit into their low-pay help-desk role, I was too old (39yo) and over qualified. Not a bad interview at all but a waist of my time. They could have filtered me better with a phone call (or reading my resume!) and I could have avoided the walk in 35'C heat. Such is life.