The core development team dissolved years ago. The last official release (Rebug 4.84.2) dropped in 2019. Without active developers, the hosting payments likely lapsed.
Download the " Rebug_4.84.2_REX_PS3UPDAT.PUP " file from the site onto a USB drive (PS3/UPDATE/). rebug.me
Using the Rebug Toolbox downloaded from rebug.me, you enabled "System Update Debug" (QA Flagging) to prevent accidental console bricks. The core development team dissolved years ago