LONDON, 2016-Mar-31 — /EPR Retail News/ — Points could be worth twice as much between 30 March–5 April 2016 The popular Sainsbury’s Double Up event, which will run from 30 March to 5 April, lets customers exchange their Nectar points for vouchers worth twice as much to spend in the following departments: Tu clothing Electricals Entertainment* Homeware Toys…