David Harrison left a comment alerting me to the availability of these papers. They have gone online earlier today.
For what it’s worth, the Metrolinx white papers are now available in draft form (look at the agenda on their site for April 25 to see them), and extension of the Sheppard subway west to Downsview and east to STC is shown in two of the 3 test concepts they mention, along with an Eglinton subway and downtown relief line along Queen. This doesn’t mean that they will show up in the RTP, but it certainly looks like they may be leaning in that direction.
I will comment on them when I have a chance to read them in detail.