I don't know what my block is, I never remember the command.
Easy:
You hopefully remember the name of the plugin: flashplugin-nonfree
For using it's update function you place in front: update-
This composed command has several options, one of them is install, so you append: -i
If you want some output in your terminal, you may select the verbosity option: -v
These options can be grouped: -iv
That's it.