An expanded flat is a sideways correction that consists of three waves down for A, three waves up making a new high for B, and five waves down for C.
I'm favoring this scenario because momentum is looking toppy and I think we need a pullback to consolidate again before moving on to new highs. A strong move to the downside will load up the shorts, particularly after seeing the new high, and add fuel to the tank for a short-covering rally to new highs around 1400.
Also, the VIX is arguing for a large move. I'm looking to go long volatility by buying puts some time today or tomorrow.