logic of expense dates range shown while entering Expense item

Summary:

We need to know what is the logic the system used to show the example of the date range to the user when the user is creating an expense claim.

It normally provides a date range and the pop up says, Enter a date between XXXXX and YYYYY

Start date - this is the start date of the employee

End Date- we are not able to identify any logic of system deriving this value.

For different users, the end date in the example is different

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