The Shared Perc 8 Controller on the VRTX Chassis does not support Virtual Disk expansion. As you indicated, the only option is to back up your data, delete existing VD and recreate another VD. There are no plans in the near future for the release of controller firmware to support this operation.
Let us know if you have any further questions.
I must say I find your answer a little bit insulting.
We have now bought a VRTX with two M630 and paid over 25 000 dollars for it. In addition, you come here and say that this system does not support resizing of virtual drives. Moreover, Dell is not planning to make support for this. WoW I think I am going over to Lenovo or HP after this. You must get the developers to priorities this. Also making a management software so it can be done from inside Windows Server. I must say that my view of Dell went down from 9 to 4 now. I advice you to get Dell to make this possible if not the system is unusable and very out of date. Even a cheep system as Synology you can do this. So get cracking.