By Kirstin Ridley and Carolyn Cohn LONDON (Reuters) – Britain’s biggest pubs group Stonegate, which is suing Zurich Insurance and two peers for 1.0 billion pounds ($1.2 billion) over lockdown losses, battled the COVID-19 pandemic “day by day, venue by venue”, a London trial heard on Monday. Ben Lynch, a lawyer for Stonegate, said the company’s 760 insured pubs, bars and night clubs at the centre of the case had each faced separate challenges, opening and shutting at differing times according to regional rules – and seeing business drop by up to 90% below projections. If successful, the Stonega…