By Charlie Conchie City investment house Jupiter has extended the exit of its star fund manager Ben Whitmore today after the announcement of his departure wiped millions from the company’s valuation in January. Jupiter, which manages just over £52bn for clients, unsettled investors earlier this year when it revealed long-standing fund manager Whitmore would be leaving the firm this year to set up his own boutique investment firm. Whitmore handled around a fifth of Jupiter’s assets and news of his exit sent shares down nearly 15 per cent in a single day in January. The company said it would bri…