BlackRock BUIDL Fund transferred 1 million USDC to an unmarked address 11 hours ago

According to Arkham monitoring data, BlackRock BUIDL Fund transferred 1 million USDC (about 1 million US dollars) to an unmarked address about 11 hours ago, and BUIDL Fund also transferred 1 USDC to another unmarked address 23 hours ago, suspected of testing the transfer transaction. The address also received 13 million USDC transferred from Circle Hot Wallet a day ago.