Everything I'm reading points to Uganda, Congo and Sudan... not Ethiopia.
It is possible that soon after the evolution of E-V38, trans-Saharan migrants carried the E-V38 marker to northern
Central Africa and/or West Africa where the more common E-M2 marker later arose and became prolific within the last 20,000-30,000 years.
[1][3]
And it was WAY before 500 BC
The downstreams SNP E-M180 possibly originated on the moist south-central
Saharan savannah/grassland of northern West Africa during the early
Holocene period. Much of the population that carried E-M2 retreated to southern West Africa with the drying of the Sahara. These later people migrated from
Southeastern Nigeria and
Cameroon ~8.0 kya to Central Africa, East Africa, and
Southern Africa causing or following the
Bantu expansion.
[4][5][6] According to Wood et al. (2005) and Rosa et al. (2007), such population movements from West Africa changed the pre-existing population Y chromosomal diversity in Western, Central, Southern and southern East Africa, replacing the previous haplogroups frequencies in these areas with the now dominant E1b1a1 lineages. Traces of earlier inhabitants, however, can be observed today in these regions via the presence of the Y DNA haplogroups
A1a, A1b, A2, A3, and
B-M60 that are common in certain populations, such as the
Mbuti and
Khoisan.
[1][7][8]