Upgrading Hard Disks in EX4100 for more space

Hi everyone. I have just upgraded from 4No 4TB Drives to 4No 8TB drives so far all has gone well. I did it one drive at a time and it seems to have worked.

However now that the new drives are installed and all the data is in place the capacity has not increased.

There is an option now to “To create a new volume from the remaining available storage space, click [here]”

There is ony one Volume at present and I am not sure I want a new volume I just wanted my existing storage space expanded.

I am running the system as RAID 10
In disk status the Disks are Healthy and show as 8TB

How can I expand the system?

Thanks in advance.

Needed to get this sorted today to be up and running again tomorrow so just copied everything off the drive to the desktops connected to it, quite a few usbs and flash cards formatted and now in the process of putting everything back onto the EX4100. Would still be interested to know if there is an easier way!