Resolved:

"That assessments to income tax may be made at any time, if required in consequence of—

(a) any alteration of the amount which falls to be taken into account in respect of excess profits tax or the national defence contribution in computing the liability of any person to income tax; or

(b) any determination as to whether any allowance is receivable by any person in respect of exceptional depreciation of buildings, machinery or plant, or as to the amount of any such allowance."