Updated return time limits revised; filing barred if a late 148A show cause notice is issued, with a specified exception. Amendment to section 139(8A) extends the updated return filing window and adds provisos: an updated return cannot be furnished if a show cause notice under section 148A is issued after thirty six months from the end of the relevant assessment year; this bar does not apply where an order under section 148A(3) determines that it is not a fit case to issue a notice under section 148.