...An agreement between the U.K. and European Common Aviation Area is crucial for the preservation of air traffic rights. We ran a sensitivity analysis on 15-day and three-month "no U.K.-EU traffic" scenarios on passenger numbers and revenue for DAA PLC, given its exposure to U.K. traffic is higher than 30%. FFO to debt in the financial year ending Dec. 31, 2019 (FY2019) could decline slightly to 45% in the case of 15-day disruption, and fall to 40% in a three-month disruption (higher than our rating guideline of 30%). Our simple sensitivity case does not account for traffic seasonality, nor does it recognize different charges payable by small, short-haul traffic versus large, long-haul traffic. We recognize that there are significant mitigating actions that airports could undertake, such as redeployment of aircraft on other routes, operating cost reductions, delays in noncommitted capex, and dividend reductions....