When using Press and Hold alt cast and instant cast, doorman places another door when releasing the key after holding the key down to remove one

[BeyondLucky]

So when you have press and hold to alt cast and instant cast it seems like the ability gets activated again when lifting off the key even though instant cast only should activate abilities when pressing the key not when you release it like quick cast. This seems like a bug and its very annoying holding down 2 to remove a door and then another gets placed when I release the key.