Description:
This is available in Balance & Reset section of the timeoff policy.

Balance:
Used to specify how the policies time off balance needs to be determined.

Set to:
This is used to provide an initial balance or starting balance in any timeoff policy which can be used to book timeoff.

Carry up to:
Web Timesheet will use the previous policies end balance & use that as the new policy's starting balance, but only up to the limit you specify.

Reset:
Select whether the amount of time off should reset, at what frequency, and to what value.

Set to:
After the reset, the policy's balance will be set to the value you enter.

Carry up to:
After the reset, the policy's existing balance will be retained, but only up to the limit you enter.