April 6th was for this year to date back 6 years until 2016.
It lapses every year at the start of the new financial year so now you can recover missed years back to 2017.
However, there is a one off chance to recover any missed years back to 2006. This runs out on 31st July 2023.
If you haven't seen any info about this then that is because it's deliberate and typical of the lack of info of the availability of many (unclaimed) benefits available to 'hard working families'.
Levelling up? my arse.............
Don't forget you will be disenfranchised at all elections from now on unless you take a photo ID with you to the polling station.
Check out the Gov.uk website for up to date Pension info.
You have until 31 July 2023 to pay voluntary contributions to make up for gaps between tax years April 2006 and April 2016 if you're eligible.