The publication of more, potentially explosive photographs of Downing Street parties now hangs over Number 10.

2. The flat

A gathering in Mr Johnson’s Downing Street flat is being investigated by police for potential Covid rule breaches, Ms Gray’s report revealed.

The event was on November 13 2020, when Dominic Cummings, then a former senior adviser, was forced out of Number 10.

The political danger from that allegation goes much beyond claims of parties held by advisers which the Prime Minister did not attend – this is an event in his own home.

The Mail on Sunday claimed that Abba songs, including The Winner Takes It All, were played. Downing Street and Mr Johnson have both categorically denied a party took place.

3. Other Boris events

In total Ms Gray revealed that 12 of the 16 events she looked into are being investigated by Scotland Yard, spread across eight different dates.

Leaving to one side the Downing Street flat gathering, Mr Johnson reportedly attended at least three other events being looked at by police.

They are the “bring your own booze” Downing Street garden event in May 2020, his alleged birthday party in June 2020 and a farewell event for an adviser in November 2020.

4. Another Gray report

A few weeks ago Number 10 hoped that Ms Gray’s report would draw a line under the “partygate” saga, getting the facts in the open before a Johnson reset moved on the agenda.

That has not happened. In fact, due to the Metropolitan Police’s request that only “minimal reference” be made to the events it is investigating, Ms Gray gave only a short “update”.

After a barrage of requests for a promise that Ms Gray’s full findings will be made public, Mr Johnson promised her final “update” will be released.

That means another Gray report is coming, most likely after the police probe is complete, which may well reveal details of what happened at the events investigated.

5. Met clears the way

Scotland Yard’s insistence that details of 12 gatherings it is investigating are kept secret was the key block on information being put in the Gray report – but it will not last.

A statement released by the Met said “this request only applied during the duration of our investigation”.

In other words, Ms Gray is free to publish everything that she has found when the police investigation – which could last weeks rather than months – is completed.

The position, if it holds, means Ms Gray and the Met will both be happy eventually to release everything they know – piling pressure on Number 10 to agree to the same.

6. The new events

Three of the dozen events which Ms Gray revealed were being investigated by Scotland Yard have not been fully reported in the public domain.

They were all leaving events. One in the Cabinet Office on June 18 2020, another in Downing Street on December 17 2020 and a third in Number 10 on January 14 2021.

The full details of what took place at each event is unclear, but it means that more details about gatherings that have sparked police interest are sure to come out.

7. Fresh Boris positions

During a bruising appearance in the House of Commons on Monday, Mr Johnson laid out a string of new public positions that are likely to be scrutinised in the coming weeks.

The Prime Minister declined to promise that he would resign if fined by the police for breaking Covid-19 laws, side-stepping a demand some Tory MPs privately have made.