This is actually interesting. It varies in the movie, even within sequences - it was an error by both continuity and wardrobe due to segments of sequences being filmed far apart. Generally, Finse was black showing, England was white showing.
Even in moment by moment WITHIN scenes it changes - black shows as he pulls grappling gun (location,) white shows as he leaps from crushed snowspeeder (studio) then black shows again as he runs below ATAT (location) then white again lasering the ATAT belly (studio shoot.)
It's maybe 50/50. The way HT has it with white showing is maybe a bit more common - for example white shows in Dagobah landing, ESB X-wing cockpit and snowspeeder cockpit (all pilots have white showing.)
I like it because it's yet another way the HT differs from the SSC (puffy location vs thinner studio look being most obvious) and it's a very cool minor detail that's right up in foreground yet no one noticed it.