PayPal Holdings, Inc. (NASDAQ:PYPL) has been trending higher, but that trend is in jeopardy. When stocks are in uptrends, the bulls are in control. If they're trending lower, the bears are in charge. A reversal day pattern is a graphical illustration on a chart of a change in leadership. On Wednesday, PayPal formed a reversal day pattern. This could mean a new downtrend is about to form. Shift4 Payments, Inc. (NYSE:FOUR) broke an uptrend line Wednesday. The bears may be about to drive the stock price lower. The break of an uptrend line is a different graphical illustration that shows the leadership is changing from the bulls to the bears.