Interview on the Market Herald with Wayne., page-26

That 5000 shares showed the same day SB started their sell down of their shares, and it was the first instant sell order to appear on Wed when that stock came out of suspension which tells me it is a bot sell order. appears in the morning and then gone by close every day.

I believe it's a marker or an indication that they still have stock, when that disappears then we know they ran out of stock.
will see if my theory is correct by the end of the week if volumes stay high.
when it is confirmed they are off the registry I will pop open the best bottle of wine I have to celebrate.