Updating SUPro file whilst in Layout

The Layout bug you described is still there, there hasn’t been an update issued since you last asked.

If you didn’t know, your subscription means you can use any subscription version of SketchUp, so if you do run until any bugs such as this that are new, there is the option to open the file in another version of SketchUp/Layout. You can actually have multiple versions installed and running at the same time if needs be.