Unannounced DJ set saw frontman play backstage at Cornwall event
Radiohead member worked on new piece titled 'Water' in 2013
'Coming Up For Air' will feature on Selway's new LP 'Weatherhouse'
The band will start work on their new album in September
Jonny Greenwood confirms plans for band to meet up later in the year
The LP will be released on October 6
Guitarist will perform at The Roundhouse in Camden
The event will take place on June 7-8 in Oxfordshire
Jonny Greenwood confirms band will meet up to discuss their future
Guitarist plays track at Wapping Hydraulic Power Station show