I’m interviewing for a job that has a similar set-up: 8:30 - 5:30 with a required 1 hr lunch break. Any idea why that lunch is required?

The hours are a red flag to me, but I’ve been a teacher for the last 6 years so I’m not sure exactly what I’m getting into. I have a 2nd interview coming up, but I can’t get a read on whether they’re trying to make sure I’m taking the job seriously, or if I’m headed into an abusive work situation. Any ideas?