HasExistingExpiry - Sets expiry only when the key has an existing expiry.
HasExistingExpiry
HasNoExpiry - Sets expiry only when the key has no expiry.
HasNoExpiry
NewExpiryGreaterThanCurrent - Sets expiry only when the new expiry is greater than current one.
NewExpiryGreaterThanCurrent
NewExpiryLessThanCurrent - Sets expiry only when the new expiry is less than current one.
NewExpiryLessThanCurrent
HasExistingExpiry- Sets expiry only when the key has an existing expiry.