You mean the 207th A359 to fly, otherwise it is the 218th A350 to fly including 11 A35X.
PS. I still don't understand why you guys insist to count A359 and A35X separately. Boeing never count variants separately, and Airbus using the same sequence MSNs for all A350 regardless what version they are. What's your point on this? It only confuse yourself when you make comments like the one above.