I wonder if Blackrock have been re-balancing their books again?...

I wonder if Blackrock have been re-balancing their books again? Someone has been selling lately? Last year on 16 Nov we received a Change of Interests for Substantial Holder where Blackrock had sold 26,254,419 shares . They had been selling form 15 July to 14 Nov & had reduced there holdings from 13.99% to 12.92%, we were only advised once they had sold more than 1%.
If you looked at the charts last year it is very similar to the chart so far this year? We were sold down from March last year & bottomed around 5c in October, then we peaked at 13.5c in March this year. Since March we have been sold down again. Maybe a good buying opportunity if we are seeing the bottom again???