Ann: Change in substantial holding from CGF, page-14

Now I'm still trying to wrap my head around this.
I did make the suggestion previously about their average price as to quantify a zone in which they wouldn't sell at a loss and where they might see a profit target, am I right in saying any purchases between now and the $1.90s will bring down their average price, however if they sell their average price reduction will be affected and they'll also take losses.
I'm just trying to make sense of it for my own ambitions to one day trade in millions of shares.
So can someone please explain to me in laymans terms how Challenger are keeping the price down as suggested earlier in this thread?