There was another roll back I can remember from EQ day but it was a merchant bug. I think it was with DoN and at one time SoE accidentally added beta npc that sells rare stuff like metallic drake scale very cheaply. Very messy roll back ensued. People who bought them were rolled back, the bazaar buyer who bought them were rolled back, bazaar seller who sold them were rolled back, people who traded with affected players were rolled back. And the selective rollback went on for like 8 hours total, hurting some people who didn't know about the issue and didn't realize until it was too late. Some lost several AA's, levels, and hundreds of legal plats in the process. Not to mention group and raid were disrupted when a player went offline without warning.
In the end it was a fiasco. People who initially took advantage of the bug and saw the rollback were able to stay ahead by quickly trading around and dropping items to be picked up, making tracking much harder.