Smidge, who heads the Sonic FanGame HQ, recently updated the site with an explanation of what happened involving the hack threats.
In mid-March, the SFGHQ forum was hacked by an individual called Manickillaz, who proceeded to make themselves an administrator and mess up the forum. After this, they threatened to hack the SFGHQ Website unless they were made an op at the unofficial IRC chatroom #srb2. Later Smidge refused the deal and deleted the entire site himself.
In his new update, Smidge estimates that rebuilding of the SFGHQ site will be complete towards the end of April. Importantly, the Sonic Amateur Games Expo (SAGE) is still planned for July, with the forum’s return scheduled to be in time for it.