I tried doing that with my dogs, but it led to them being annoyingly clingy as their general dinner time approached because they knew they could be fed suddenly

I tried doing that with my dogs, but it led to them being annoyingly clingy as their general dinner time approached because they knew they could be fed suddenly at any time. So I switched to using a phone alarm that marks when it's time to feed the dogs. I can easily change the time it rings to adjust their meal times, and they remain patient because they know that they won't be fed until they hear that sound.