Check other substantial holder notices from Blackrock - they are one of the prime manipulators of the price and have been playing silly buggers from day 1 (regular small volumes in a prior notice were evidence they are bot trading AVB).
I believe personally (unfounded and just an opinion) that their strategy while the price has been below their original entry point has been to use their trading power to average down / make small profits. After all they need to show their investors they are making interim returns on their money
AVB Price at posting:
7.4¢ Sentiment: None Disclosure: Not Held