This is my worst time as well! I've combatted it two ways.
1. I eat a large snack or mini meal before leaving work around 3:00. This usually works quite well.
2. I feed my family dinner at 4:30 or 5:00. That way I'm only clock watching for an hour to an hour and a half.
I could eat a full meal at 3:30 or 4:00. I experimented one day when the kids were gone for the evening. I ate dinner at 4:00 and I was not hungry the rest of the evening. If I could just eat an actual meal at that time I'd be good. That's what my body naturally wants. I think it must naturally wind down around 6:00 and this is nature's way of telling me eat now so it has time to work it off. I'm also a morning person, so my body tells me to go to bed early.
Just a theory.