Nope, this seems to be something of a common thread in a lot of cases. I can understand it to a degree. Just like many situations that have a lot of emotional content, time passes in a very strange way.
I am not sure what you might have experienced in your personal life, but if you are shocked about something strongly or are experiencing something else with a lot of emotion in some ways it seems that time flys by very quickly, OTOH, you might find that you have looked at your watch 3 times in the last 10 minutes. Other times, you stop for 5 minutes, but the clock says 2 hours have passed. This can happen if you receive word of the sudden death of a loved one, or perhaps the birth of a baby that you are involved with.
If BC did this, and did not have it planned out in great detail, he was shocked and working as quickly as possible to cover the tracks, get rid of the evidence and he had to get this done before the kids woke up! Wow, he would have had a busy morning! He has to figure out where to put the body, lay some false trails, clean the house... in this situation, I think the calls to him about HT were pretty inspired.
I lean strongly towards the TOD being between 1 and 2 AM, due to the amount of things he had to get done, and I think that unless it was preplanned for weeks, he probably had to take some time to get a grip and figure out what he was going to do.
Another point, the killer has to do all of these tasks under great stress and a short period of time. They think they have covered all of the bases, but LE has ALL THE TIME IN THE WORLD to examine everything in minute detail. I would think it is nearly impossible to get away with killing someone close to you, since you are going to be a suspect almost automatically. This does not always apply to a stranger killing someone, most of the time they get caught because the cannot keep their mouth shut.
CyberPro