The filing deadline is April 15, 2020. And you can get an extension until October 15, 2020----but any estimated tax due has to be paid by April 15.
No. Once you e-file it is like dropping it in a U.S, mailbox. You cannot get it back.
Unfortunately it is most likely you will not be able to stop the refund from coming in since you already filed your return. The only thing you can possible do is call the IRS and speak to a representative and see if they can change your refund from direct deposit to a paper check which will give you more time since the IRS will need to print and mail the check.
If you want to try that you can call 1-800-829-1040, but please note this is their busy time and you will be placed on hold. Click here for more information: https://www.irs.gov/help/telephone-assistance
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