Hi @Hope180
@Mike-And-Jane0 have pointed out the only way to apply custom check in check out days is by using a Rule Set to override the default settings for the entire year.
It's think it's easier to use the multicalendar to create and apply rule sets to the calendar and you can easily tell the Rule Set is applied to specific dates on the multicalendar by the shading. The regular calendar doesn't show the
shading, so its hard to identify the dates the Rule Set has been applied to.
A Rule Set will only effect the dates you apply it to and overrides your calendar default settings. Below is a guide that has screens shots and explains how to do that. Thank yourathto create and use Rule Sets
Use Pro Tools To Set Custom Checkin/Checkout & Min Stay
https://community.withairbnb.com/t5/Community-Guides/Guide-How-to-Use-Pro-Tools-amp-Rule-Sets-to-Cre...