This is not a huge surprise given the announcement of the new UT. OT Lead Victor Blanco posted the following in the UE4 forums:
This project gets discontinued, Epic new Unreal Tournament is all we wanted from Open Tournament, so OT doesnt have a reason to exist now. The OT team and chat will still be there, for discussions and help regarding UE4.
We may never know for sure but it is quite possible that OT actually forced Epic’s hand into doing a new UT. The fact that they are just starting RIGHT NOW is quite interesting. Victor and the team will just be moving over to the new UT so all it not lost.
The OT forum is already down so I will be removing site links to that project and focusing on the new UT. All hail the new UT!!