There have been multiple countdowns so far.
Either they are fake decoys and there is only one real one (The booms? How many boom events so far? What happens when the 6th occurs?) occuring "behind the scenes" in a larger timeframe or yet to occur.
Or they are distinct countdowns pertaining to sub-operations. Single arrests, or perhaps the booms? Or just important movement cues?
They are not going to broadcast what they are actually doing. The enemy can see it just as easily as we can. It is likely misdirection for the enemy and simply to signal to us that something is happening. But don't expect to be able to figure it out.