Aerad Africa Supplement
Pag. COM-9
IATA In Flight Broadcast Procedure
Ch. 3.6 - GPS or RNAV equipped aircraft
Says :
"IATA Technical Policy Manual states that when flying in areas where in flight broadcast procedures are used, and when using accurate navigation guidance systems, all aircraft should fly offset 1 NM right of nominal track"
Searched in Jeppesen too, didn't find.
IATA Tech Policy Manual is not published on the web, you can buy it
here.
HVIII