Celebrities are taking part in the charity stunt to raise awareness about amyotrophic lateral sclerosis
'Sheezus' singer set to bring live show to UK in November and December
Allen will tour with the pop star for a string of dates in the US next month
Writer Helen Fielding has changed story for West End production
Singer pretended she was being arrested by officers at the Gold Coast Airport in Queensland
The singer reflects on her experiences at the festival where she met her husband
Singer also lashed out at male-dominated music industry in new interview
Singer is critical of third studio album, saying she 'can't wait' to record new music
Childhood, Crystal Fighters and Rudimental also played the first day of the event
Allen drafted in at last minute to replace band in their headline slot this weekend