Inconsistent behavior with function / callable overrides

Mypy appears to allow a callable variable to be overridden by a function declaration (a symbol defined using def statement) if the signatures match and they are in different suites (e.g. one in the "if" block and the other in an "else" block). If the order is reversed, mypy generates an error.

Is this intended or a bug? It strikes me as inconsistent.

def func1(cond: bool):
    if cond:
        def a(a: int, /) -> None:
            return None

        b: Callable[[int], None] = lambda a: None

    else:
        a: Callable[[int], None] = lambda a: None  # Mypy error: Name "a" already defined

        def b(a: int, /) -> None:
            return None

Use the provided func1 example as the entry point; compare mypy's diagnostics when the def declaration and Callable assignment occur in each branch ordering. Done means the differing behavior is explained and, if confirmed as a bug, both orderings are covered by a regression test.