The red part is probably thermovent which used for the electronic equipment in fuselage,similar to its analogue on J-35.
If this is a real photo they definitely need to bump up securityCan anybody learn anything more from this image that we didn't already know from the previous sightings? Not really right? Good thing for China atleast and we just got a super sexy picture. I'm surprised people can just wall jump an airfield in China of all places though.