Sorry about bothering you, I wanna understand it clear. What do you mean by "wrongly" created? What is this failsafe for? And what's the purpose of replacing the block?
@Dhranios I'm not sure of what you mean. I'm not talking about the "Time" NBT being 0 (causing the falling block to despawn), but about the block below (not an entity) being replaced with air. The only thing about the falling block is the change in the "Time" NBT to value 1, but that isn't the main issue.
Can confirm in 22w24a.