Can the person chargeable with tax pay the amount of demand along with interest and reduced penalty after the issue of notice under section 74(1) or 74(3) , but before the adjudication and issue of order under section 74

Yes. The person chargeable with tax under section 74(1) or the statement under section 74(3) can pay the amount of tax along with interest under section 50 and a penalty equivalent to 25% of such tax within 30 days from the issue of notice [Section 74(8)]. The person chargeable with tax shall inform the proper officer of such payment in Form GST DRC-03 and the proper officer shall issue an order in Form GST DRC-05 concluding the proceedings in respect of the said notice. Please note that on such payment, all proceedings in respect of the said notice except for proceedings under section 132 shall be deemed to be concluded.

(ICAI FAQ PUBLCIATIONS 06-09-2017 Determination of tax not paid or short paid or erroneously refunded or input tax credit wrongly availed or utilized by reason of fraud or any willful misstatement or suppression of facts: FAQ NO. 13)