Additional Chuck Berry Session between Sessions 70 and 71

Fred Rothwell's Long Distance Information: Chuck Berry's Recorded Legacy (Music Mentor Books, 2001) is the ultimate book for any serious Chuck Berry record collector: All Berry sessions, all the songs, all the session musicians, where to find which song if ever released, and tons of additional stuff.
First published in 2001 the book consists mainly of a 240 page commented "sessionography", a list of 93 recording sessions Chuck participated in between 1954 and 2000. For each session Fred lists the musicians and the songs recorded, whether released or not. For every song he shows a few main records containing it. He also fully describes and critizises every recording.
Chuck Berry's recorded legacy is not complete yet, though. After publication of Fred Rothwell's book we found out about an additional recording session which took place prior to or in early 1975:

Prior to 1975 Chuck Berry must have recorded a 30 seconds radio spot telling to get off hard drugs. The recording was made available as part of the National Association of Progressive Radio Announcers' (NAPRA) "Hard drugs awareness movement - Get Off". The radio spot was distributed to radio stations on an album called Get Off II (NAPRA-2, 1975). For details see the section on Radio Show and Promotional Records.