I recently heard some more research on the Andrew Huberman Lab Podcast from Dr. Gina Poe that further supports the ideology that consistent sleep (and wake) times are incredibly beneficial to us as humans.
Human growth hormone is released in our bodies all day and night our entire day and night. In the first stage of our sleep, however, is when the biggest release of human growth hormone occurs. If you miss that first sleep stage (due to going to bed later than you usually do), you miss the biggest release of human growth hormone in our 24 hour day. These big releases are incredibly important for body and brain health functions such as protein synthesis, memory retention, and the removal of waste in our brains.
If you usually go to sleep consistently around 10pm, this big release of growth hormone will be released within 1-1.5 hours of you initially falling asleep. However, if you go to sleep at 11:30 or midnight one night, you miss out completely on that big release. You cannot make up that release; it does not get pushed back further into our sleep stages. In other words, you cannot go to sleep later than usual and expect to capture all of the hormone releases that you usually do. This is due to our synchronized biological clocks; our cells are ready at certain times to expect hormone release.
So, as consistently as possible, try to get to sleep around the same time every night!