They say simple returns in phase one those with credits and then married and more complex in phase 2 so what is head of household claiming eitc is its no mention of the specific filing status related to the Irs phased approach to recalculation for those that filed early before the 10200 tax credit
As stated on this IRS website - https://www.irs.gov/newsroom/irs-begins-correcting-tax-returns-for-unemployment-compensation-income-exclusion-periodic-payments-to-be-made-may-through-summer
More complex corrections will begin upon the completion of the first phase and involves couples filing as married filing jointly.
Go to this IRS website for unemployment exclusion FAQ's - https://www.irs.gov/newsroom/2020-unemployment-compensation-exclusion-faqs-topic-a-eligibility
You're eligible to exclude the unemployment compensation if it was received in 2020 and your modified adjusted gross income (AGI) is less than $150,000. The modified AGI for purposes of qualifying for this exclusion is your adjusted gross income for 2020 minus the total unemployment compensation you received. This threshold stays the same for all filing statuses, regardless of whether you're married and file a joint tax return (it doesn't double to $300,000).
If your modified AGI is $150,000 or more, you can't exclude any unemployment compensation from your income. This applies to all filing statuses.
If you claimed EITC you would be in the second phase. The IRS news release that DoninGA referenced says "The first phase of adjustments is being made for single taxpayers who had the simplest tax returns, such as those filed by taxpayers who did not claim children or any refundable tax credits." EITC is a refundable credit. It makes your tax return more complex, regardless of filing status, because they have to recalculate the EITC as well as the unemployment exclusion.
Just be patient and check the IRS site once or twice a week for an update using the original refund amount :