Section 86(4) in The M.P. Vanijyik Kar Niyam, 1995
(4)When service is made by post, the service shall be deemed to be effected by properly addressing, prepaying and posting by registered post with acknowledgement due the notice or summons or order and, unless the contrary is proved, the service shall be deemed to have been effected at the time at which the notice or summons or order would be delivered in the ordinary course by post.
