If you have a Office365 calendar, here some information to help you create all-day event to inform Julie about any changes in your availabilities :
Tick "All-day" to create an all-day event : your calendar will be easier to read, both for you and Julie, especially if you want her to schedule meetings on this/these day(s).
Choose is you want this/these day(s) to be showed as "Available", "Busy" or "Away" depending if you want Julie to schedule event or not (cf How to communicate changes in your calendar to Julie article)
If, for example, you are working from another office every Wednesday, you can add a recurrence to your event with the "Repeat" option.
This is a view on Windows, on Mac the view change.