Tribunal held that a perusal of sub-section (3)(b) of S. 124 shows that the jurisdiction of an AO cannot be called in question by an assessee after the expiry of one month from the date of which he was served with a notice under sub-section (1) of section 142 of the Act or after completion of assessment, which was to be earlier. In the present case, the assessee had not challenged the assumption of concurrent jurisdiction by the JCIT within the time stipulated in the statute. in the absence of any objection filed by the assessee during the course of assessment proceedings or within the time stipulated under section 124(3), the ground raised by the assessee was dismissed. (AY. 2009-10, 2010-11, 2011-12)