I had DS have a bedtime from under 2m old. We would aim for 8pm, bath at 7.30. It wouldn't always work, but that was "bedtime" (unless Dr Who is on, that's DS's treat night and he stays up).

Now bathtime is 7pm (unless a new Dr Who is on, he's in a new place and excited or just had a day sleep and DH didn't wake him so he's not at all tired and happy being up and playing) and bedtime around 7.30 - he's usually around 7.25-7.45 these days, 8pm at the latest.

At 15m old it was more 8-8.30 that he gave up and went to sleep, but we were aiming for 7.30 still.

I found that a BF too late would gear him up again; if he didn't feed to sleep then it was trouble. But he'd dropped all but the morning feed by 15m so that was no longer an issue.