1The Postmaster General shall, on suspending the authority, serve on the person to whom it was issued a notice informing him of the suspension, of the grounds thereof and of his rights under the subsequent provisions of this Schedule, and further informing him that if he does not avail himself of those rights the Postmaster General may revoke the authority:
Provided that where it appears to the Postmaster General that it is not reasonably practicable to serve the notice on the said person, the Postmaster General, in lieu of serving the notice on him, shall take such steps, by advertisement or otherwise, to bring the notice to his knowledge as appear to the Postmaster General to be reasonable in the circumstances.