I remember reading that here specifically, but can't remember who posted it unfortunately... but what's rattling around inside my head as true is that being in the player assistance program is frozen, can't be traded, demoted and counts against the cap. Once the player has been in the program long enough to meet the requirements of LTIR, the team can then designate them as such and get relief with the same stipulations as relief from a physical injury.
If there is any chance the player is coming back, the worse thing in the world I think you could do, would be to use that cap relief. Let's just say that we had done this with Girard. Could you imagine how impactful that would have been on his mental wellbeing to be going through treatment trying to get himself better and stronger but also know that he's been replaced on the roster. That would be pretty f***ing cold.