Just to update concerning battery charging issue. Apple agreed there is a known issue with battery charging and replaced the unit. Having received new unit charged at 100% I used for approx 3 hours and battery drained to 8%. After 4 hours charging it reached 23%, however I had to stop charging as it became extremely hot, not just very warm but almost too hot to touch. Have put on charge again today and after 3 hours has increased by 5%. Battery once again very hot. Have brightness turned down and location off.
Waiting for Apple to comment