Briton Johnny Gibbs has been in Australia for six months, surfing and working part-time – like countless other young people drawn to the country’s pristine beaches and laid-back way of life. He is one of thousands that venture Down Under on so-called “working holiday visas” – a chance to work, and play, in Australia for as long as three years. But the future for some backpackers is now in doubt, following the government’s announcement of plans to cut the number of visas issued – and detain...