Previously, if you use the coinbase wallet to purchase BTC, then you would have to wait 6 days to get the BTC unless you transferred money to Coinbase Exchange

Previously, if you use the coinbase wallet to purchase BTC, then you would have to wait 6 days to get the BTC unless you transferred money to Coinbase Exchange and purchased them directly. This simply removes that step and executes your buy order against the Coinbase Exchange presumably.