Hello, I am not sure if this is a bug or if I use it wrong way. But when I create block with two identical block attributes everything look ok. I Can insert it to drawing, set the value (both will change). But when I use "Synchronize attribute (UY)", only one will stay. It would be fine if both would stay. But I understand that you probably use tag as identification.

To reproduce the problem just open the attached file and press UY