According to the IRS FAQs here:
If you enter your bank information in Get My Payment any day until noon on Tuesday, your payment date will be available beginning the following Saturday in Get My Payment.
If you enter your bank information after noon on Tuesday, your payment date should be available beginning the Saturday after next in Get My Payment.
There may be times when your payment may be sent by mail because the payment was already in process before the bank information was entered. If this is the case, then typically it will take up to 14 days to receive the payment (standard mailing time).
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