Testator can revoke or Alter Will anytime when he/she is competent to dispose of his/her property by will.

By revoking executed will testator can execute fresh will or alter the contents of the Will by adding a codicil to the same will.

Only precaution Testator should take is that he/she should register the fresh will if earlier will was register and also register codicil if the will to which codicil is executed registered.