It looks like the trades in S&P500 are mainly to capture theta or a bit of vega short play. Most are short put spreads and the ones that are bought seem like later buy backs of the short leg.
Also, there are a few iron condors with long the wings, short the body... typical for short vega/theta capture.
the calls were traded around ATM at the time... puts were all OTM spread. I don't see any directional stuff happening, so must all be theta/vega.
that 14 call on ultra short VIX... it's all short vols they've been doing...
Looks like they weren't very well positioned for BREXIT...