A test of Intelligent Data Placement Feature in ASM

In the test , I create a tablespace in ASM and further create a table on the tablespace. 
In order to verify what Oracle says that
"When you modify the disk region settings for a file, this action applies to new extensions of the file, but existing file contents are not affected until a rebalance operation."
I then try to modify the disk region settings for the datafile and then query the table to see whether the reads still occurrs in the cold region, the the result is in the hot region which confused me, Here is the detail things of the test: