(A Fairly Exhaustive) Timeline

[jeremy spencer]

March 22? - When in Munich, Green, Fleetwood, Spencer and a road manager are invited to a party at a hippie mansion, called Highfish Commune, located in a forest. (It has been said that Green was invited not for company, but so that filmmaker Rainer Langhans and Uschi Obermaier could get in contact with Mick Taylor. Langhans and Obermaier wanted to hold a Bavarian Woodstock, with Jimi Hendrix and The Rolling Stones performing.)
Green unwittingly drinks wine spiked with LSD. Green stays at the party for 24 hours, spending time jamming in a basement. Dennis Keen, the road manager, gets bad vibes and leaves. Spencer and Fleetwood cook eggs. At a concert the next day, Green feels "marvelous, fresh and not grubby". Later, Green says that at Highfish, "he went on a trip, and never came back." His overuse of LSD may have contributed to his schizophrenia.

This is actually 1970. Just a few days before he announced his leaving FM one morning after a gig in Zurich.
And 'Marvellous, fresh and not grubby'? Wow. The acid must have really reversed his doors of perception.