I think they get pressured to discharge the person after a certain amount of time. { by ins?} Usually they can only treat for the time frame Rx'd by the MD.

Maybe MD asked for an update and results so far?
and further tx can't be justified right now?

And maybe PT has done as much as they can for now.

If you feel more PT is needed and helpful maybe a new place or therapist might be a good thing.

the old one door closes and another one opens theory...