BlackRock, the world's largest asset manager, is selling Bitcoin to buy Ethereum, signaling a potential shift in investment strategy.BlackRock has sold 182 BTC worth $11.34 million and purchased 7,574 ETH worth $18.52 million.This move could potentially trigger a bullish rally for Ethereum and spark another altcoin season.Analysts are optimistic about the altcoin season, with indicators suggesting a significant price increase for altcoins.