NO ... you can file now. Her amending will not ever allow you to efile the return ... your ONLY option it to mail in the return for the 2020 tax year.
And make sure you have the right to those items ... only the custodial parent get those items. If you are the non custodial parent according to the IRS rules then they filed correctly.
If you are the custodial parent where the child physically lived for more than half the year (183 nights) then:
When you enter the dependent, you say that he/she is "Your child" (not you and your spouse if remarried),
he/she lived with you the whole year,
“no” the child did not pay more than half of his/her own support,
"yes", you have a custody agreement,
and "yes", the other parent is claiming this year.
That will give you the EIC, Child Care Credit and Head of Household filing status if you otherwise qualify.
The child would be listed as "non-dependent EIC & Dependent Care only".
The other (non-custodial) parent can claim the child’s exemption and child tax credit only and needs a signed 8332 form to do so.
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There is no such thing in the Federal tax law as 50/50, split, or joint custody. The IRS only recognizes physical custody (which parent the child lived with the greater part, but over half, of the tax year. That parent is the custodial parent; the other parent is the noncustodial parent.)
Who can claim the exemption and credits depends on who is the custodial parent. (By the IRS definition of custodial parent for tax purposes - this is not the same as the legal custody that a court might grant.).
The test that the IRS uses to determine the custodial parent is where the child lived for more than 1/2 (or greater part) of the year. The IRS will go so far as to require counting the nights spend in each household - that person is the custodial parent for tax purposes (if exactly equal and more than 183 days - The custodial parent is the parent with the highest AGI, if less than 183 days then neither parent has custody so the child cannot be claimed by either parent). And yes they are that picky.
See Custodial parent and noncustodial parent under the residency test in Pub 17
https://www.irs.gov/publications/p17#en_US_2017_publink1000170899
Only the Custodial parent can claim: (Child would be listed as non-dependent EIC & CC only)
-Head of Household
-Earned Income Credit
-Child Care Credit
The non custodial parent can only claim: (Child would be listed as dependent)
-The Exemption
-The Child Tax Credit
But only if specifically specified in a pre-2009 divorce decree, separation agreement or the custodial spouse releases the exemption with a signed 8332 form - after 2009 the IRS only accepts a signed 8332 form that must be attached to the non-custodial parents tax return.
Note. If you are the non-custodial parent filing your return electronically, you must file Form 8332 with Form 8453, (U.S. Individual Income Tax Transmittal) for an IRS e-file Return. See Form 8453 and its instructions for more details. This must be done within 3 days of your e-filed return being accepted by the IRS.
