So what does this mean for them... and for you?
The crunch point is the end of this month, as 31st July is the payment date for those people who complete a self-assessment form. They have to pay half at the end of the year and the other half by the end of July.
HMRC sends out reminder letters indicating what is due, and hammering home the expensive danger of missing the deadline - and the fines and interest that can be imposed on anyone missing the deadline or failing to pay.
However, this year HMRC failed to order enough of the paper it needed in order to print the letters, so hundreds of thousands will not be getting a letter until well after the deadline.
Apparently the problem was that the number of statements due to be printed has soared and no-one told the genius tasked with ordering the paper. It's just the kind of seamless internal communications we would expect from the government, and the level of competence in particular we have come to expect from HMRC.
What does it mean for you?
On the plus side HMRC has said that those who don't receive the letters will have another 30 days to pay before they start accruing interest. However, if you complete a self-assessment form, and haven't received a reminder, the advice is to act as quickly as possible to find out what you owe, so you are not left with a nasty surprise at the last minute.
You can find out how much is outstanding on your account by checking your details online. And it's worth doing that as soon as possible, as we know just how well these HMRC systems stand up during times of heavy demand.
As ever, your best bet is to go to the ends of the earth to ensure you don't make even the slightest slip - and pay the price for it - while at the same time assuming everything emanating from HMRC is subject to disaster.
So what do you think? Let us know in the comments.