"Even without it they still have to get 2/3 of the shares."
Nope. With the SRP in effect, they could not accumulate anything over the allowed limit(20%) without triggering it. After Dec 01, they can opt to take up any amount (25%, 35%, 50%) that they have committed to them. They might not get 2/3, but 50% plus one will ensure they get it all eventually.
Regards
K