Selection of new earlier date should be treated as new check-in date.

[bixbarton]

From ChrisW and Joanne.

When you select a valid date that is before the current check-in date, we want to assume you want to change your check-in date - so make the newly selected date the new check-in date and then slide the pointer over to the check out date.

[rapuckett]

This should already be achievable by listening implementing protocol and interacting with CXTabView according to whatever logic you prefer.