Are you asking about the 2019 refund or the 2020 refund or the Stimulus Checks?
You can only change it in Turbo Tax when you actually file your return which won't be until early January. But then Turbo Tax will just hold all the returns until the IRS opens efiling around Jan 27. For the Stimulus Checks the IRS hasn't put out any info yet on how to change the bank account numbers.
