Form 16a

Form 16A is issued to person other than income payment done of salary to the individual, in the given case if the Salary is given then on the demand of the employee Form16 is to be given.... and in case of Form 16A it should be provided if any Tax is deducted.

Its is not compulsory to issue FORM16 (You right FORM16A) if you have not deducted any TDs.

If employee demanding you can give him salary certificate of that 4 month, write their salary paid by your organisation during that 4 months.

Its is not compulsory, If employee demanding then prepare manually. 

Form 16 should be issued only if Tax (TDS) is Deducted or deductible.

As no tax has been deducted, Form 16/ Form 16A is not required to be issued..