ESA wrong dates on ESA subnission

Long shot I know but front page of DWP IB(IS) response has date of decision 26/06/2012..
medical was 10/07/2012…

Can I get that thrown out on a technicality?

I’d be careful here.  The days of tribunals overturning decisions on technicalities are largely long gone thanks to R(IB) 2/04, paras 72-82.  Tribunals should rectify defects of form as opposed to defects of substance.  Where a decision has been properly made a mere slip of the pen will not invalidate it.  If the correct date of the decision can be ascertained from elsewhere in the appeal bundle then that will enable the tribunal to proceed.  If it cannot and there is no presenting officer, and no other evidence as to its correctness is produced at the hearing, then the tribunal will simply adjourn and direct the Department to produce it.  Finally, representatives have a duty to assist the tribunal.  So if a representative identifies such a defect and sits on it, raising it for the first time at the hearing then he is likely to find himself on the receiving end of the displeasure of the tribunal.