I don't think you get it. A block universe in which nothing happens cannot possibly exist since it is clearly falsified. We observe change, do we not? So speaking of loops within a block universe is like arguing about how many angels can dance on the head of a pin. Is it me, or do other people go out of their way to be illogical?
Change can be viewed as a sequence of distinct immutable observer-moments, like frames in a movie, and nothing forbids them to form a loop.