These conflicts arise every time because they have to (and glad they do). There's no actual split between "development" and "release management". Both have same goal - to get the best-of-the-art delivered to the user. Different motivations, perhaps, but goal is the same. Different paths to accomplish same goal, but they tend to balance each other.
Equilibrium is the key word. Like in everything else in life.
Now, saying that "Conflicts like this should never happen"... They do, and I'm glad they do - that means people actually worry about. Both developers, and "release managers".