It's a little known gotcha that the Treasury Solicitor must approve, for example, acceptance of equipment off contract when it cannot be certified correctly. That might include where the contractor turns out not to have the necessary approvals. A common and topical breach is when no MoD specialist signs-off on equipment with explosives or propellants, such as ejection seats.
Breaches are so common, they probably dream up some arbitrary sum once in a while to make a point. But they do tend to avoid cases where there has been a political overrule and MoD told to award contracts to unsuitable companies in favoured constituencies.