This is very worrying. It seems like ESA have started a game of chicken with the Commission over the budget for the ground segment of the Sentinels. Given the financial and political situation in Europe I am not convinced the EU will take the long view. I must confess a sympathy for ESA: the EU was to have secured the funding needed for operating the Sentinels and has played politics with the issue rather than railroading the member states into providing the funds.
Even if the issue is resolved you have to wonder if ESA HQ in Paris will now be wary of EU partnership in Space.