The iOS Parcel app doesn’t write expected delivery dates to an iCloud calendar but only to a local calendar. So I just created a Shortcut Automation that runs at 9am daily, copying Parcel created events to an iCloud calendar (shared with my wife). No way to share Personal Automations so here’s a screenshot.

a screen shot showing a shortcut that copies events from the Parcel Calendar to a iCloud Shipments calendar. It checks for duplicates, too.