Assessment time limit extension after draft order references allows completion after administrative directions, altering limitation computation. Forwarding a draft assessment order and subsequent receipt of directions from the higher authority excludes the intermediary period for limitation computation so that the remaining normal time available at the moment of forwarding continues to be available after directions or expiry of the objection period; multiple drafts may be sent before the normal statutory limit but not after, administrative directions can be issued within the normal time limit on matters not previously examined or objected to, enhancements cannot be made in the reference stage but may be pursued by administrative directions or by invoking reassessment/revision provisions where permissible, and fresh evidence is admissible only on issues objected to.