Key events ordering when publish date is exactly the same

[georgeblahblah]

We order key events based on their first published date (or created date if that isn't available). However, some live blogs have two key events with exactly the same first publish date, e.g:

~ % http "https://www.theguardian.com/politics/live/2024/may/17/keir-starmer-jeremy-hunt-rishi-sunak-conservatives-labour-uk-politics-live.json?dcr&page=with:block-6646453d8f086b5d4c8c0095&filterKeyEvents=false" | jq '.keyEvents[-2:] | .[] | {id, title: .title, blockFirstPublished: .blockFirstPublished }'
{
  "id": "6646453d8f086b5d4c8c0095",
  "title": "Welcome and opening summary …",
  "blockFirstPublished": 1715933187000
}
{
  "id": "66470c638f086b5d4c8c0610",
  "title": "Jeremy Hunt attempts to draw general election dividing line over tax",
  "blockFirstPublished": 1715933187000
}

However, the body blocks reveal a different ordering:

http "https://www.theguardian.com/politics/live/2024/may/17/keir-starmer-jeremy-hunt-rishi-sunak-conservatives-labour-uk-politics-live.json?dcr&page=with:block-6646453d8f086b5d4c8c0095&filterKeyEvents=false" | jq '.blocks[-2:] | .[] | {id,title,blockFirstPublished}'
{
  "id": "66470c638f086b5d4c8c0610",
  "title": "Jeremy Hunt attempts to draw general election dividing line over tax",
  "blockFirstPublished": 1715933187000
}
{
  "id": "6646453d8f086b5d4c8c0095",
  "title": "Welcome and opening summary …",
  "blockFirstPublished": 1715933187000
}

In this case, where the key events have an identical first published time, we should take the ordering from the body blocks.