Currently, an appointment from 23:00 to 1:00 the next day is shown as a mutli-day appointment in the top bar in the Android version of Proton Calendar.

To me, it is important that, when planning, I can see such appointments in the regular agenda view. This prevents me from making overlapping appointments.

Google Calendar does this by showing appointments of less than 24 hours regularly and appointments of 24 hours or more are shown in the top bar.

Also, the desktop view of Proton Calendar already has this behaviour. But the Android version does not.