Timing of tax liability redefined to the tax period when the completion certificate or first occupation falls. The amendment substitutes two phrases: replacing 'in whose case the liability to' with ', who shall ', and replacing the clause on when liability arises with a timing rule that liability arises 'in a tax period not later than the tax period in which the date of issuance of the completion certificate for the project, where required, by the competent authority, or the date of its first whichever is earlier, falls.'