Nasa
In answer to your questions:
a) They won't. Period. Forget it.
b) You leave that to me. I've been running around the country in a new 208B fitted with the new King KGP560 TAWS, which includes a terrain awareness display on the multi-function display, and it's brilliant - possibly one of the greatest safety enhancements in GA for decades. I've shown it to CASA. I'm optimistic they too will understand its significance and make the minor amendment necessary to CAO 20.18 to permit its use in light turboprops on commercial passenger IFR ops. It's a lifesaver.