my Bank told me the same thing. real fast, but a transfer took 8 days to send money to myself. so it depends on how both banks send and receive that transfer and also if the transfer will include a week end. note: banks only transfer money on weekdays. and they may require the real money in their bank before you have access to it.
Just FYI, the new law doesn't apply to Zelle. They're not an app and they don't hold your money. It does apply to PayPal and some other ones though. Zelle has been trying to get the word out about the law not applying to them.