Blackrock depths min level is 42 (server was set at 50)
Note: TBH from what I remember on the official it was better doing this towards 50 rather than 42 but that was a long time ago
SQL:
REPLACE INTO `access_requirement` (`mapId`, `difficulty`, `level_min`, `level_max`, `item_level`, `item`, `item2`, `quest_done_A`, `quest_done_H`, `completed_achievement`, `quest_failed_text`, `comment`) VALUES (230, 0, 42, 0, 0, 0, 0, 0, 0, 0, NULL, 'Blackrock Mountain - Searing Gorge Instance?');
Note: TBH from what I remember on the official it was better doing this towards 50 rather than 42 but that was a long time ago