The claim is plausible because corroboration search results repeatedly mention 250 million USDC mint events on Solana by Circle around the relevant period, including the Economic Times liveblog snippet and Binance Square snippet. If nine such mints occurred within a week, that would total about $2.25 billion. However, I could not directly fetch or validate any of the provided X posts or the BlockBeats page, and none of the fetched sources in this run directly confirms the exact one-week aggregate of roughly $2.25 billion. Helius' Solana stablecoin overview supports plausibility of large USDC supply on Solana but not the specific weekly increase. Therefore, there is not enough directly validated evidence to confidently rate the statement true.