Are me eyes deceiving me? The left nozzle looks squarish whilst the right nozzle looks more "roundish". If true, then there might a hint of 2DTVC of sorts; or testing of two different engine configurations (the latter being highly unlikely). Or just a case of some flaps at top of left engine...
Also, whilst not definitive, the belly did not appear to show the deep trough / channel in the light grey prototype
I won‘t try to read too much into blurry Images
