• The Downing Street staff hosted a party for James Slack (Boris Johnson's former chief of communications) on April 16, 2021.
• Official records indicate that Slack resigned from the civil service in March 2021.
• Slack is now the Sun's deputy editor.

Boris Johnson's former communications head, James Slack, left the government almost a month before an official lockdown-busting leaving at Number 10 was completed, according to records.

The Cabinet Office released Transparency Records showing that Slack's last day as a Civil Service employee was March 19, 2021.

Downing Street called it a "farewell party" on Friday morning. It was held on April 16, 2021, the day before Prince Philip's funeral. The Queen was seen sitting alone at the event.

The Telegraph reported that Slack thanked several press advisors and aides at the party on Friday, April 16 in a farewell speech.

Insider asked the Prime Minister's deputy spokesperson about this inconsistency, but she was unable to respond immediately.

According to the Telegraph, Number 10 employees joined via video link.

Later, alcohol was opened and the group mixed with another group to celebrate a different member leaving the Downing Street garden.

Slack issued a statement regarding the incident, saying that he was sorry for the anger and hurt caused. This should never have taken place at the time it did. I am deeply sorry and accept full responsibility."

On Friday morning, the Prime Minister's deputy spokesperson said to journalists: "It is deeply regrettetable that this occurred at a time when there was national mourning." Number 10 has apologized to the palace.

The spokesperson didn't explain specifically what "this" meant.