At the time Ben Elliot, joint chair of the party suggested the PM borrow to pay the costs.
The PM then came up with the idea of a blind trust, again funded by donors. But the Cabinet Office could not sort the proprieties.
According to an email leaked to the Daily Mail, the Tory donor Lord Brownlow then contributed £58,000 "to cover the payments the party has already made on behalf of the soon to be formed 'Downing Street Trust'" - which was never formed.
The Tory Party had seemingly already paid back the Cabinet Office for the decorating bills it had paid on the PM's behalf. And the PM has now paid back the Tory Party.
We don't know when the PM paid the Tory Party, or how he found the funds to do that when he didn't have them in February of last year.
We also don't know whether Brownlow has also been repaid. And we don't know who in the Cabinet Office and among Johnson's advisers knew what was going on.
Cummings says he was clear with the PM from last summer that he should dig into his own pocket, by taking out a personal bank loan, to pay for the furnishings and decoration of his home.
There are so many unanswered questions. And prima facie there are an astonishing number of disclosure rules that have been breached, along with rules of common sense.
For what it's worth, a source tells me: "Ben Elliot tried to stop the madness repeatedly".
He seems to have failed.
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