It can only be shorts. Every single investor is currently way down and if they wanted to bail they would just do it. What is happening is a large stack of orders at the ask which drops every time the pps does, been happening for the last 2 weeks. There isn't big buying pressure currently so the shorts stack the ask and watch and every time the pps drops, they drop their order down. It is very manipulative as they likely have buy back orders set very low from previous shorts so essentially they are manipulating the pps so they can make a killing off of their original short sales...
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