Japanese citizen multiple entry

I understand Japanese citizens can travel to China for up to 15 days with no visa.
But does this apply if it is a multiple entry trip?
And is there a minimum period required between two entries?

I (UK citizen) will pass through China on a trip to a third country with my girlfriend (Japanese).
We will enter China on April 7th and exit on April 8th.
We will re-enter China on April 10th and leave on April 11th.

I will apply for a multiple entry visa. Can she make the entire trip within one 15-day permission period?
Or will she need some type?
Many thanks
Dan