It's not entirely incoherent, since time is relative to the geometry of spacetime and your trajectory through it. OP's original statement could be referring to the time coordianet in two separate frames of reference, so we might say that time (for us) is being reverted all the time (from someone else's perspective).

It's even theoretically possible to have closed-timelike curves in general relativity, which means that time would literally loop for some set of set of observers. Any matter riding on these curves does have to have periodic dynamics, so in a sense it would be evolving and then reverting endlessly.

To be fair though, the existence of such solutions to Einstein's equation is seen as problematic, since they raise questions of time-travel paradoxes and such. Also, I have only a passing familiarity with the details of the physics in such spacetimes, so take what I say with a hefty grain of salt.

and what does "for a second" mean?

Good point, I haven't thought of that.

I replied to GP, outlining a potential resolution. Thought you might like thinking about that kind of thing, so letting you know directly.