Section 69 in The Appellate Side Rules of The High Court at Calcutta
69. When an advocate retained to appear for any party to an appeal is prevented by sickness or engagement in another court, or for any other sufficient cause, from appearing and conducting the case of his client, he may appoint another advocate to appear in his place, so that his client may not be unrepresented at the hearing, but such advocate shall not so appear unless he shall have first obtained the special permission of the Division Bench, or the Registrar, as the case may be.
