Everyone will be in the same situation here so, in theory, no-one will be unduly affected.
AQA will have two possible responses based on past behaviour
1. They may discount this question completely i.e. give everyone full marks for this question automatically. This is their standard response when papers have been leaked
2. They may say that, as everyone had the same, incorrect information, no changes to marking will be necessary.
Any decision will not usually be known until the results day though if this error gets traction in the media, AQA may be forced into making a statement sooner.
Complaints from the school as a whole would be more effective than anything done by an individual