Hi Prashant,
There is no restriction with respect to the number of days of leave that one must take in order to claim LTA. For example in West Bengal, around the Puja time there are successive holidays and an employee may not take PL but still avail LTA. LTA can be availed of during any leave including study leave, casual leave and special casual leave
The criteria for being eligible for tax deduction is that the money must have been spent and documentary evidence ought to be available with the employee.
Also the assessee employer is under no statutory obligation to collect evidence to show that its employee(s) had actually utilized amount(s) paid towards leave travel concession(s)/conveyance allowance - Ref CIT v. Larsen & Toubro Ltd. [2009] 181 Taxman 71/313 ITR 1 (SC). The onus of proving that the employee travelled and is eligible to claim tax exemption is mainly on the employee.
Employers while assessing the travel allowance claims, do not need to collect proof of travel to submit to the tax authorities. Though it is not mandatory for employers to demand proof, they still have the right to demand documentary proof depending on its policy. The Judgement of Supreme Court, cited above, has only moved the responsibility from the employer to the employee, the assessing officer can still ask for the employee to provide details of travel.
Regards
R Bhatnagar