Under Section 3 of Arbitration and Conciliation Act  the relevant legal provision, how is the receipt of written communications determined unless otherwise agreed by the parties?

As per Arbitration and Conciliation Act: Section 3 Receipt of written communications—(1) Unless otherwise agreed by the parties— (a) any written communication is deemed to have been received if it is delivered to the addressee personally or at his place of business, habitual residence or mailing address, and (b) if none of the places referred to in clause (a) can be found after making a reasonable inquiry, a written communication is deemed to have been received if it is sent to the addressee's last known place of business, habitual residence or mailing address by registered letter or by any other means which provides a record of the attempt to deliver it. (2) The communication is deemed to have been received on the day it is so delivered. (3) This section does not apply to written communications in respect of proceedings of any judicial authority.