Bedtime time?

My 10 week old has been sleeping through the night for about 3 weeks now (yahoo!) from 9:30-10:30pm ish all the way until about 8:30 (give or take an hour either way). But the past 4-5 nights he has been taking a long nap from 6-8:30 (because I don’t let him sleep later because I need him to sleep at bedtime) and I wonder if maybe I should just be putting him down for the night then? I’m not sure if he’s just sleeping well because it’s a contact nap and if I were to lay him down in his bassinet he’d wake up. But I also don’t want to lay him down earlier and then have him be up for the day at like 4am. I start work again in 5 days so I don’t want to experiment and mess up the time we start our day but want to know when it’s typical for the 10pm bedtime to turn into something more like 7pm or 8pm.