Premium and Memory surcharge

Happy End of Year to you ;>) 

I have a question, please , concerning Premium Memory Surchage and eviction Mechanism 

I think when a dataset needs to be refesh or a report is consumed, the dataset is loaded into memory

For the same dataset we can be on the double of necessary memory if it is solicited at the same time in rendering and in refreshment

However, there is a memory capacity constraint (25 GB for Capacity P1 in my company & 6 refreshes on parallel)

To free memory, an eviction system is in place and  If no eviction is possible, the dataset goes to WAIT ROOM

For the rules of eviction I observed this one:
- A dataset on memory but not consumed via report requests  is evicted after 3 minutes of inactivity

But, are there other rules please with kinds  of prioritization notions  ?

- Can a dataset required to view a report (rendering) induce  Pausing or Evict for a dataset that is currentlty being refreshed ? or It has to wait (WAITING ROOM)?

- Can a dataset required for ad-hoc refresh evict a dataset being refreshed?

Merci beaucoup and Best regards

Christophe