I mean, by this logic, every piece of new canon is retroactive continuity (which is essentially what MM says when he states that he's "bound by canon"). The new information in Research Station Gamma changed the setting as it was explained in Kinunir which changed it from the LBB's - let alone the changes that came with MT, then TNE, then Milieu 0, etc etc etc
I also saw the "Our Psions vs Their Psions" as a pretty logical extrapolation of how things would work. Given that we know that the Imperium does utilize psions (military programs and research programs) logically they have to go somewhere when they muster out - into the employment of the nobles houses seems like a logical step. Nobles with the right clearance already know they exist, and have the same reasons to want them "handy" as the IN (et al), it also keeps them as a resource for the Imperium rather than as free-range troublemakers.
D.