European flying to China - Hong Kong - China - Abu Dhabi

Hi, is it possible to use 72 hours visa free transit in following situation of flight routings:
- Abu Dhabi to Shanghai - stay for 3 days
- Shanghai to Hong Kong - stay for 1 day
- Hong Kong to Beijing - stay for 3 days
- Beijing - Abu Dhabi - flying back

Question is simple, is there any limitation on period of getting free transit in the cities? And will be above routing possible?
Thank you