The CRTC has not announced any such policy that I'm aware of. And given that they'll soon be going through a change of administration at the CRTC, I doubt we'll see any major policy announcements until afterwards.
With the DTV roll-out, the goal was to free up spectrum by using more the efficient digital technology. That goal has been achieved, and we'll see an auction of the 700MHz band likely next year.
Some broadcasters have already committed to rolling out digital to rural transmitters.
For example, Global TV (now owned by Shaw) will be converting all transmitters to digital under their "tangible benefits" agreement. I believe the timeline for completing this roll out is 2015 or 2016.
Obviously I'm in support of a policy to have broadcasters convert rural transmitters to digital. Especially now, as the newly licensed "Free HD" satellite service (now "BluSky") has backed away from the business model that would have them distribute free broadcast channels to rural viewers. Though my understanding is that Shaw offers this service.
If there is a local transmitter that you hope will convert, I would write the station/network a polite letter indicating your desire to see them go digital. Have your friends/neighbours do the same.
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