If they were just trying to assemble the best team, they should probably trade Knapp (assuming he has more value than Rupp) and bring in a veteran back-up catcher, while leaving Rupp in AAA. But, they are still trying to figure out what they have in Alfaro and Knapp, and obviously they still like Knapp's bonus offense, especially on a thin bench.
Anyway, the real issue is I think they need three catchers on the 40 eventually, and also Rupp could have some trade value mid-season if he doesn't now. He's more valuable than Curtis or Florimon.
It will be interesting to see how the rotation shakes out but I'm not sure ST matters all that much. Pivetta's been considered a lock all along as he did make progress over the course of last season, despite ugly numbers. Thought it's also true that Lively doesn't really need more time at AAA. Going with Hutchison to replace Leiter as long man and also 5th starter, just for April, maybe does make sense, if you find the spot for him.
It's hard to know how much to read into the Phillies putting Florimon on the 40. If they were ready to go with Valentin or even if they preferred Flaherty, why sacrifice Alvarez in the first place?