Cats have an internal clock that is crazy accurate.
LOL, we have one of those automated feeders, and...when they aren’t out there an hour before it goes off, they are there five minutes before.
My wife thinks they can hear some pre-noise it makes that we can’t hear...but I don’t think so.
I think they have an internal clock that is closely calibrated to their sleep times, which means...they probably only have about a half hour a day to calibrate to!