According to a twitter posting by DX-coffee (@dxcoffee), a group of Latvian radio amateurs shall operate briefly from Mount Athos in late May 2015 (May 19-25). The operators are YL2GM, YL2GD, YL3CW and YL2KA and shall use a collective callsign SV2/YL7A.
No further information is available for the time being, but a press release is expected tommorrow or the day after.
UPDATE 2015-05-16 12:30 UTC: According to a post on DX-world.net by SV1DPI, who is usually well informed about Mount Athos, the SV2/YL7A team don't have the required permit from the Holly Community Council. I wonder how the ARRL shall react when they apply for DXCC acceptance.
UPDATE 2015-05-16 13:30 UTC: The following DX web sites have published relevant information:
Check the above sites for up-to-date information and for possible press releases by the YL7A team.