With the note that I'm from EU, so some social habits my differ, if someone, not just a manager have to reach me I have a VoIP phone and there is NOTHING to schedule up front. Someone call, I answer.

The "scheduling" part is NOT about WFH vs in office but working without defined timeframes LIKE in the office. If you state: you should be available at your desktop from your home between HH:MM and HH2:MM2 these days per week anything will be the same.