Expanding PR4100 storage

I have just added a new second 14TB drive and the 1st 10TB is now at 95% so the alert light on my PR4100 is red. Is it possible to change the red light to blue now that there is an additional 14TB ?

Also now that I have two Jbod volumns, on the Mycloud dashboard it has combined the 300GB remain from my 10TB to the 14TB, so 14.3TB is shown, which is what I wanted. Is this similar to expanding the 10TB which I thought wasn’t possible when using two drives without losing data?

If I were to add say a file which was 500GB would that fill the 1st 10TB first before continuing to write the remainder to the 14TB ?

Is it possible to add files from the 10TB to the 14TB to get rid of that red light if it cannot be changed back to blue?

Thanks

Thank you for your explanation. I am now in the process of configuring the 14TB volume and will move 250GB of files onto that drive from the 10TB and will then map the new drive.