Conversation so far:
What is the band Gong 'proper'?
Did the band, Gong release any albums during 1969-1971?
The band, Gong released Magick Brother and Camembert Electrique.
When did Gong 'proper' release Magick Brother?
Magick Brother is the debut studio album by the progressive rock band Gong released in March 1970 on the French BYG Actuel label.
What year was this when Gong's album Magick Brother was released?
Magick Brother is the debut studio album by the progressive rock band Gong released in March 1970 on the French BYG Actuel label.
Did the album Magick Brother by Gong win any awards?
Did the Gong band tour in support of their album Magick Brother?
The re-born Gong played its debut gig at the BYG Actuel Festival in the small Belgian town of Amougies, on 27 October 1969
When was the debut gig at the BYG Actuel Festival for the band Gong?
The debut gig at the BYG Actuel for the band, Gong was in 1969.
Were there any lineup changes during this period after Magick Brother was released for the band Gong?
Houari left the band, Gong in the spring of 1971 and was replaced by English drummer Pip Pyle.
Any other lineup changes for the band Gong besides Houari leaving in 1971 and replaced by Pip Pyle?
By the end of the year Pyle had left the band, Gong, to be replaced by another English drummer, Laurie Allan.

Question: When did they join the band?
Self-contained rewrite: When did Laurie Allen join the band Gong to replace Pyle?