The first half of the concert, to include Mozart's Symphonies Nos. 39 and 41, will be recorded, reproduced, and available for purchase on CD at the end of the evening. Unsold CDs will be offered through the group's web site.
The CDs will be packaged in a gatefold sleeve (presumably printed in advance) that will include program notes for the concert.
According to the site, the CDs are "first of what will become a series of live, unedited recordings of concerts given by John Eliot Gardiner and his choir and orchestras," which also include the Monteverdi Choir and Orchestre R_volutionnaire et Romantique.
Rock groups have sold live recordings after concerts for several years, but the practice is only now spreading to classical music. The G‹rzenich Orchestra of Cologne, Germany, announced last fall that it would start selling CDs after concerts. That orchestra offers the entire performance on CD, but there is a delay of a few minutes before the recordings are available.