There are at least three actual tapes of Empty Pages in circulation. One is the FM-SBD from Gaelic Park 8/26/71. A second is an AUD from Gaelic Park 8/26/71 (i.e. the same performance in an AUD recording) And a third is a different performance, and AUD, which circulates labeled "Chicago 8/24/71". This is somewhat confused by the fact that there are also copies of the 8/26/71 FM-SBD in circulation misalabeled "Chicago 8/24/71 SBD" and also copies of the 8/26/71 AUD of Empty Pages in circulation mislabeled "Chicago 8/24/71 AUD". However, there is also, as noted above, an AUD recording in circulation of a performance of Empty Pages that is a different one from 8/26/71, which is labeled "Chicago 8/24/71." If as Dwight relates, the main AUD master in circulation from Chicago 8/71 does not include an Empty Pages, then this must mean that there is a second AUD master. This second AUD master could have ended up labeled "8/24" rather than "8/23" because the other tape was circulating with the former date. But it could also be circulating dated "8/24" because that's the way the master is dated. In which case it would provide evidence for the 8/24/71 date. But obviously the question of this date is still quite murky. However, as noted, there is indeed a 2nd performance of Empty Pages in circulation, labeled "Chicago 8/24/71."