Which is the correct deadline 31 January or 1 March?

Submitted my self assessment and then received a tax calculation letter from HMRC on 22 Nov 2022. It said in bold letters please pay your outstanding tax by 1 March 2023. Today I received an e-mail from HMRC self assessment support saying I need to pay by tomorrow 31 Jan ! Which is correct?

Hi Redfizz,

If you registered after 05/10/2022, then your filing date would be 3 months and 7 days from the date you were registered.

The original payment date should still be 31/01/2023.

Our Self Assessment helpline can confirm this.

Self Assessment: general enquiries

Thank you.