I dont like this route. The only value for the WoSign keys for a whole year would be issuing certificates with a doctored notBefore date, and they can't do that publically.
It's an attempt to avoid instantly breaking all the sites across the web using WoSign/StartCom certificates. A year should give customers enough time to learn about the issue and switch providers. Meanwhile, WoSign can't sign up new customers or renew existing ones (at least, not if they want those new certs to work in Firefox).
They could start reselling certs from a CA. That way their customers wouldn't have to sign up with a different CA. Then a year later, they could get everything back to normal.