MIS to NRML conversion of hedges

While I understand that Zerodha has OI limitations and in the present setup, there is no range limitation for MIS order and that MIS to NRML conversion of buy legs have been disabled to prevent carrying forward of positions outside allowable range. But there has never been a restriction on OI created when it is a hedge for a short position. So I don’t understand why Zerodha is blocking MIS to NRML conversion of a hedge position when I already have a NRML short position. If this is allowed, option sellers with 1.5-2L buffer can easily bypass the range limitation.