Etrade must be heavily short HHSE. Etrade Management's decision to restrict HHSE to "call-in buy orders only" confirms that they are protecting themselves or their VIP clients who are short HHSE. This same manipulative practice happened recently with Robinhood (and other brokers) when they limited the online purchase of XXX, XXX and other Reddit stocks that they had heavily shorted.
Once the Form 10 is filed in the coming days, Etrade and all HHSE shorts will be squeezed.