We have a SharePoint Calendar list. When the user clicks on the plus sign "+" to add an item, it needs to be disabled for additional entries on that day.. We should not see the "+" anymore to add an item for that day.
If the user adds an item through the list view, the date picker appears and the user selects the date. The next time an item is added, any dates are grayed out out that were previously used. If an item is deleted, the date can be used again.
I have added some screen shots to help show what we need. There area also some fields on the form that we need permanenty removed. thank you