Not sure about 24 hour sessions under the stairsCountess, since my stamina seems to flag round about 3 am, at which time the sessions in the bar were usually still in full swing. However,I DO recall taking part in a singing session in the corridor outside the ladies in 2004, which I think was initiated by John Waltham, which was still going strong when I left it at 3am in the morning - the acoustic was fantastic, and there was suggestion of congregating inside the gents the following night to carry on the session (as the acoustic in there was supposedly better). Sadly that never materialised as the organisation of the foray in quesetion never quite got off the ground! (I think we ended up in the comfort of the Octagon Room instead).