Confusion about the difference in usage between present perfect and past perfect to give news

Question

The book titled Oxford English Grammar by Swan says it's common to use present perfect to give news. However, when we give or ask for more past details, the book suggests the readers to use simple past.

Here's an example:

The cat has eaten your supper. She took it off the table when I was out.

The other book (Advanced Grammar in use by Martin) says

'When we give an account of a sequence of past events we usually put these events in chronological order using the past simple. If we want to refer to an event out of order – that is, an event which happened before the last event in the sequence we have written or spoken about – we can use the past perfect.'

In my opinion, the order of events of the example I've given above is:

I was out -> The cat took my supper -> She ate it.

Does it mean both present perfect and past perfect are appropriate here?

Answer 1

If we want to refer to an event out of order... we can use the past perfect.

I went out, and when I returned I found that the cat had eaten the supper which I had left on the table.

The past perfect is used here because the eating took place before the speaker returned home. If the speaker then gives the news to another person who arrives home, they can say, as in Swan's example:

The cat has eaten your supper.