11U.K.Where income from any source for any year of assessment would become payable to a custodian but for the fact that no income from that source is available for payment in that year, but, apart from the operation of the law relating to trading with the enemy, income tax would nevertheless be chargeable in respect of income from that source for that year, the provisions of this Part of this Schedule shall have effect as if income from that source had been available for payment in that year and become payable to the custodian.