Yes, do put an "appointment" on your calendar. Apologize for not being able to make the standup, and then each week give a complete update in an email or slack

Yes, do put an "appointment" on your calendar. Apologize for not being able to make the standup, and then each week give a complete update in an email or slack message. In my experience, many people who are happily awake at 8:30am purposefully ignore the fact that other people have different sleep needs, and only a scheduling conflict can convince them to give you leeway. I have several coworkers who have "kid pickup/dropoff" on their calendars to enforce a hard start/end time, or even just "workout" or "commute." Having a vaguely unmoveable scheduling conflict is the only way to maintain a reasonable sleep schedule without a lot of pushback.