If you remove a 'teaser' image from an article in TCMS, and re-flow it up to Blox, it seems that the teaser image won't go away. You actually have to remove it from both system versions. Is that a bug?
There are actually a handful of things that suffer from the same bug. I've been trying to compile a list so I can submit a ticket about it.
In the meantime, if you edit the body copy (such as just inserting a space at the end of a paragraph) it'll force an update on the items that don't trigger one on their own.
Customer support service by UserEcho