Hi,
There is no statutory obligation on the employee's side that leave should not be availed during the notice period. For instance, sickness during the notice period cannot be neglected just because the employee serves the notice period. However, in general, most employers insist on completing the notice period without leave.
Leave without information during the notice period
Leave without information during the notice period is different, as it amounts to misconduct. Therefore, you cannot apply the same scale for all cases, and it depends on the situation; a decision may be taken accordingly. If an employee proceeds on unauthorized leave for more than 2-3 days, the employee can be advised to extend the notice period or consider the period of absence as leave without pay.
Leave-informed cases
For leave-informed cases, while 1-2 days of leave can be neglected, anything beyond that, the candidate can be advised to extend the notice period.