Good morning GJ I hope I do get a sunny day to make up for the last couple of extremely cloudy days.
The mandatory filing of 3 monthly accounts data with HMRC is no myth and the papers are not wrong. There's various HMRC & government documents about this but the shortest one confirming this is:
https://www.gov.uk/government/...utumn-statement-2015
The proposals are going out for consultation fairly soon. The intention is that for self assessment tax people it will be brought in from April 2018, for VAT returns from April 2019, and for companies from April 2020.
This government know that as every self employed person keeps up to date accurate computerised accounting records, there is no issue, no extra work for people, it's just a matter of clicking the "send" button at the end of the quarter. They see no problems. There's an e-petition about this which will get debated in Parliament but the governemnt has zero intention of changing its mind. You might want to read their response on the petition. It's not very nice reading, particularly as it says that the consultation will be about what sanctions to implement.
https://petition.parliament.uk/petitions/115895