maybe U could do it with a query, i tried this one and works ok
UPDATE restaurants SET schedule_data = '{"monday":[{"open" :"08:00","close" :"19:00"}],"tuesday":[{"open" :"08:00","close" :"19:00"}],"wednesday":[{"open" :"08:00","close" :"19:00"}],"thursday":[{"open" :"08:00","close" :"19:00"}],"friday":[{"open" :"08:00","close" :"19:00"}],"saturday":[{"open" :"08:00","close" :"15:00"}],"sunday":[{"open" :"00:00","close" :"00:01"}]}' WHERE schedule_data IS NULL
just make sure to change to your desired schedule, you can play according with your scenario