According to the IRS, the delay will be only for taxpayers who receive the EITC (Earned Income Tax Credit) or the ATCT (Additional Child Tax Credit). The Additional Child Tax Credit is a different credit from the Child Tax Credit (CTC) (so be sure which one you have). The ACTC can generate a refund; the CTC cannot.
The IRS says:
"Expecting a refund? Some refunds must be held until February 15.
- According to a new tax law change, the IRS cannot issue refunds before February 15 for tax returns that claim the Earned Income Tax Credit or the Additional Child Tax Credit
- This applies to the entire refund, even the portion not associated with these credits.
The IRS will begin to release EITC/ACTC refunds starting February 15. However, the IRS cautions taxpayers that these refunds likely won’t arrive in bank accounts or on debit cards until the week of February 27. Read more about refund timing for early EITC/ACTC filers."
Note that there are other relatively rare cases in which your refund is delayed or held; follow your refund's progress at https://www.irs.gov/refunds