The smart folder is filtered by date/time -- it's in app settings under smart folder, and also in the "slide out drawer" in the smart folder itself.
Other than that, yes, it's same messages.
"Sometimes when I swipe right to delete in my smart folder the message is not deleted in my inbox but is removed from smart folder"
Yes, I'd be very interested in hearing if you discover some sort of pattern.
Anyone else seeing this or similar?