If I changed my direct deposit for the second stimulus check via the email they sent after your deposit gets rejected, will the third go to the same one?

Your stimulus payment (EIP3) will go to the last information the IRS has on file. If you changed your direct deposit information with the IRS, then your EIP3 should go to that account.

Per the IRS, if your payment can’t be delivered to you for any reason, it will be returned to the IRS. To get your payment reissued:

• Set up direct deposit with Get My Payment. After your payment is returned to the IRS, your payment status will update to “Need More Information.” You can then choose direct deposit to a:
  • Bank account
  • Prepaid debit card (must be reloadable; contact the card issuer for information)
  • Alternative financial products that have a routing and account number associated with them
• Update your address with the IRS. The easiest way is to file your 2020 tax return with your current address, if you haven’t already done so. Once we receive your current address, we will reissue your payment.

For other ways to update your address with the IRS, see How do I notify the IRS my address has changed?