With today's PTR build, Blizzard seems to be changing some data entries for Siege of Orgrimmar items, including Heirloom items from Garrosh Hellscream. While these changes don't confirm anything, it is possible that it is a change to prepare the Mists of Pandaria raid to be the new Timewalking raid. Making Mists of Pandaria the next Timewalking raid would be the perfect opportunity for a new source of the now unobtainable Garrosh Hellscream Heirloom weapons. These items were previously all removed in a different PTR build and are now returning. The items in question are all the original IDs from Siege of Orgrimmar normal difficulty items. To those unfamiliar, with the raid difficulty changes from Patch 6.0, all Siege of Orgrimmar loot received new item ids. This patch was the addition of the Mythic difficulty and ever since then, items started using bonus ids for changes between item versions. Until WoD, all different item versions, like Heroic, Warforged, or Heroic Warforged, had different item ids. This change was made because of the bloat in the list of items. For instance, Revelations of Y'Shaarj, which is item id 112940 post-WoD Pre-Patch, actually had six different item versions in Mists of Pandaria:
Revelations of Y'Shaarj for Heroic, old Normal difficulty. Item id 103920. Revelations of Y'Shaarj for Mythic, old Heroic difficulty. Item id 104654. Revelations of Y'Shaarj for Normal, old Flex difficulty. Item id 104903. Revelations of Y'Shaarj for Raid Finder difficulty. Item id 105152. Revelations of Y'Shaarj for Heroic Warforged, old Normal Warforged difficulty. Item id 105401. Revelations of Y'Shaarj for Mythic Warforged, old Heroic Warforged difficulty. Item id 105650.You can see how a system like that is
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