If Mr. Winter is from the Government Digital Service here in the U.K., I think he would be your best route. Certainly, the GDS would be the best people to speak to on this. As far as I'm aware, the political parties don't have any access to the data. Indeed, the data is not kept for very long actually by government itself, so that has not posed a problem thus far. The bigger problem is whether parliamentarians have access to it.
