FIVE hundred days from next Saturday, Hong Kong returns to Chinese sovereignty. The South China Morning Post will devote a special section of next Saturday's edition to a survey of what lies ahead, with contributions from leading Hong Kong figures. We would like to hear readers' views of how the coming 500 days can best be handled, in the best interests of the territory. Please address your letters to The Editor, South China Morning Post, 28th floor, Dorset House, 979 King's Road, Quarry Bay - or GPO Box 47, Hong Kong. We look forward to hearing from you.