9 is the max number a load check will show, but that doesn't mean there are only 9 seats available to be sold.
It could mean 9 but it could be more.
The only things you can definitely say about the above figures are
Outbound
There are at least 9 seats in upper and 9 seats in premium that virgin will still sell.
There are at least 9 seats in economy as well but given its showing 9 in the second lowest economy fare bucket, you could surmise there are still a fare amount of economy seats available. Nobody except VS knows how many seats are in each bucket code.
Inbound
There are only 6 seats in upper that virgin are willing to sell with only 3 available in the lowest z fare code
In premium and economy all fare codes are showing as 9 so you could surmise that are still a fare amount of seats available in each cabin.
The showing of 9's (which by the way, you don't add up) is one of the more difficult one to be able to make more definite predictions on the exact number of seats available.
Hope this helps a little. - someone else might be along to shed a bit more light on the subject
David