The early tax return deadline was yesterday WHY

[essayer]

As I have about £1000 to pay for 2020-21 I thought I'd take advantage of HMRC's easy instalment option (adjusting the tax code and paying it via PAYE). Sat down with a coffee and thought I'd be nice and organised and submit it this morning instead of 11.50pm as normal. Then I see this:



FOR GOD'S SAKE IT'S THE 30th?? WHY IS IT THE 30th AND NOT THE 31st LIKE IT IS IN JANUARY

Now I have to liquidate other investments* to pay this off**


* sell the dog
** late, as usual