when upgrading from 2.1.0p15 to p16 MKP-plugins were downgraded to a previous version.
I confirmed this on a clean site:
2 versions of the plugins are available, version 1.1.0 is active, 1.0.0 is inactive:
After upgrade to CMK 2.1.0p16 the old version 1.0.0 is activated again.
So after an update to 2.1.0p16 is it is currently a good idea to ensure the correct version
activated (or remove old plugin versions before the update), especially when using the bakery.