The Mac, iPhone, and iPad are all signed in and iCloud in Preferences show all three are logged in to my Apple ID.
I have 12 of my own calendars along with using holidays (subscribed) and birthdays. Unchecked is Siri Found In Apps, Reminders, and Clearing (whatever that is). Calendar is also checked (who knows what that is for). Everything shows that is checked except Phases.
Calendars only began being synced to iCloud last month. Years ago Phases did show then but I unchecked. Recently (before using iCloud sync) I decided I wanted them to show again and found they wouldn't appear.
A change made in one device will change on all devices which shows they are all linked to iCloud.
I have refreshed the calendar list on all devices with Phases still checked on all three devices calendar list
Phases is still not showing after refreshing on all devices. The Mac Calendar in month view is the easiest to see if phases were visible
Attached is a screen capture from iPhone which shows the same calendars that are on all three devices. Can't show the remaining calendars below Phases in one screen capture.
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