Exclamation [Q] Filesystem strange behavior

I am a security researcher, my project is to secure data on android devices by live replacing /data/ container with encrypted one.
I did this many times on different devices and with P601 I am encountered a problem.
The problem is - device ignores filesystem changes like there are no of them.

For example - if you unmount/move /data/ on any other android device - system will hang up, because it will lose connection with applications, cache and user settings. But if you do so on Samsung Galaxy Tab 10.1 2014ed - nothing will change! Android will just ignore replacement/remove and will still read/write to data partition wherever it is. How this is works? It is connected with KNOX framework?