Could not get it to see updates to the composer.json file of a module I was working on

Thanks for this great module. I was setting up the composer.json file of a module I am working on.
I ran drush composer-manager update and the autoload info showed up as expected in the autoload_namespaces.php file
But then after I update the modules composer.json file to fix a bad setting on my part it would not cause a change there.

Was there a command I needed to run other than drush composer-manager update ?

I ended up installing Monolog just to see if that would force a rebuild and it did.

Thanks!