Someone else will be more exact, but I'm prettty sure that the T20 license has more than 2 and less than 3 years left to run ...
... and then Hunter will need to:
1. Stop Publishing.
OR
2. Convert it to OGL.
OR
3. Renew the license through Mongoose (or Marc).
So nothing is happening soon, and there are still options when the license expires. As an example, Avenger chose to stop publishing 1248 Era material and to convert Golden Era material to the MgT OGL when their license expired in November of 2008.