The set pays tribute to the Southern rock pioneers and their extraordinary body of work, and will be available as a 10LP or 5CD box set or digitally.
Gregg was born on 8 December 1947 in Nashville, one year the junior of brother Duane, with whom he would co-found the mighty blues-rock institution the Allman Brothers Band.
History has tended to overlook the festival that was bigger than Woodstock, Monterey or the Isle of Wight.
Gregg Allman, a founding member of the Allman Brothers Band, He passed away Saturday (27 May) at his home in Savannah, Georgia; he was 69.
Butch Trucks, who co-founded The Allman Brothers Band in 1969, passed away on 24 January, 2017 aged 69.
Brothers and Sisters was spreading the Allman family name on 8 September 1973, becoming the Allman Brothers Band's only US No. 1 album.
The band were flying high when the dreadful news arrived, on 29 October 1971, that Duane Allman had been killed in a motorcycle accident.