When did you start allowing wiggle room around bedtime?

My 9 month old has finally settled into a good bedtime and sleep routine of 7pm-7am. Recently, we’ve encountered some eye rolls and tension at family events when we excuse ourselves early to make it home in time for bed. A lot of “oh you won’t let her stay up just this once? But it’s grandma’s birthday… You’re so regimented, loosen up…”

Am I being too regimented? Will a one-off late bedtime mess us up for days like I fear?

Thanks for any advice you may have 🩷