Full withdrawals, on the other hand, are when you remove the entire balance, including the 32 ETH, from the blockchain. This means that your validator will stop participating in the block validation process. Full withdrawals won’t happen automatically because the validator needs to send a message to the blockchain to add itself to the exit queue. This takes time and will be released gradually.
Source: https://www.coindesk.com/tech/2023/03/29/shanghai-is-nearing-but-when-can-i-withdraw-my-staked-eth/?utm_medium=referral&utm_source=rss&utm_campaign=headlines