Complex sentence: Monday to Saturdays, five trains a day head from Giggleswick southbound to Skipton and Leeds and northbound to Morecambe with four each way on Sundays all year since the May 2011 timetable change (an improvement on the former twice-daily winter frequency).
Split into simpler sentences: Monday to Saturdays, five trains a day head from Giggleswick southbound to and Leeds and northbound to & Morecambe. Four trains run each way on Sundays throughout the year since the May 2011 timetable change (an improvement on the former twice-daily winter frequency).