I need to add 1 residence as soon as I have somewhere to put it so next chapter I will need to upgrade 40 magic residences and 12 magic workshops. That means I would need 52 blueprints. Even with FS doing 10 chests per week I think I can only hope for 1/2 of that. I'm thinking there is no way I could wait long enough to save up 1 year worth of blueprints. They've got me on the hook for at least an $80 diamond buy and probably more
Now if Inno was as money grubbing as some say then they actually could let us upgrade blue residences & workshops twice. That would be a nice spike in Inno's cash flow
Of course that would be pretty unfair to players who don't buy premium residences since they already can only upgrade 1/2 way in this chapter and then have to wait until they are way into the chapter to get to upgrade the rest of the way.
Adding: If they ever get the spell for upgrading event buildings that will divert blueprints too