maybe it was a bluray frame in SSE 1.6?
Only missing LPP frames were replaced with the bluray.
I didn’t work on this section of the film for the SSE, but chances are good that the guy who graded it was consulting other post '85 sources during the color grading - like the GOUT and the Japanese Special Collection - and none of these references had this brightness so it was ‘corrected’ for the SSE.