I'm confused about the rise from 2084 as it didn't reach logical upside targets. This chart is just one possible explanation.
If the rising wedge idea is valid, then (from the a,b triangle) the rise to 2277 will be wave 'a'. Wave 'b' should ideally fall to overlap the peak at 2213.
I should have explained that (from the a,b triangle) the move upwards to 2277 is an exact abc where c=1.618. That seems too much like coincidence and reinforces the idea that a rising wedge might be in play.
Interestingly this rising wedge idea for SPX matches the same potential pattern in FTSE.