As expected the leg down commenced in full swing today;
It opened up below the AB=CD PRZ, usually a good sign that the move will continue.
On the 3min chart it tested the 113%BC (the lower range of the PRZ on the daily chart) from below within a penny.
Subsequently it traded between the 78.6 and the 88.6%XA levels (daily chart), literally within a penny of these levels.
In the last hour selling increased and SPY closed right at the February 2nd low.
Break below the February 2nd low, brings the 113, 127, and 161.8%XA levels of the daily chart in play.