Yes it works. I have seen people use VEB on larger volumes but be aware that the first one is full and can take quite some time so do your first ever in the weekend
12 TB does seem a bit close. It all depends on the daily churn. Another thing is that after the 7 days, a merge needs to happen and I fear that you won't have enough space to be able to do that merge. What type of backupdrive is it? Is it a volume inside the server? Is it a different storage? Can you expand it?
Personally I would wait a little bit longer since we are getting close (as Anton stated in one of his latest digests) to the GA version of VAW
My 2 cents