Identity Protection PIN

When the IRS recently opened up applications for an Identity Protection PIN to anyone, regardless of Identity Theft history, my husband and I applied for and received our IP PINS in January, 2021. 

 

The Identity Protection PIN notice that came with our numbers states, "Congratulations, your 2021 Identity Protection PIN is:  XXXXXX."   Hence my confusion:  Are these IP PINs for our 2020 tax return, or for our 2021 tax return?

 

Thank you, in advance, for your help on this!