We have found an article posted today, which talks about the participation of the Ukranian Air Force at the RIAT airshow. It is very likely a yes for the participation:
Lt. Col. Jonathan Nixon, commander of the Royal Air Forces of the United Kingdom, watched the execution of demonstration pilots in Mirgorod aviators on a Su-27 fighter aircraft, did not hide his enthusiasm:
– I was watching the preparation of Ukrainian pilots to participate in the aviation show on the Su-27. With great pleasure I can state that the aerodrome program meets the safety standards and is very exciting. I am convinced that the British public will be pleased with the performance of Ukrainian pilots. In addition to the fantastic flying program, my memories of Ukraine will remain incredibly friendly people and the hospitality I felt. I really hope to come back here in the future….
It should be added that Ukrainian military pilots this year increased the number of aerobatics and added new elements to the complex, which are performed at small and extremely low altitudes….
On the international aviation show “The Royal International Air Tattoo – 2017” Ukraine will represent the Su-27 mass production aircraft, not specially prepared and refitted for air shows.
UPDATE
RIAT organisers confirmed as well