Bond for sez sales

We had sez sales in July , Sep & Nov amounting 80lakhs approximately.

Due to lack of awareness, we raised the bond in oct & bank guarantee in Nov under rule 96A . But by the time , new gst rules have come up. I personally had discussion with the GST inspectors of my jurisdiction.

But , they say as per the new rules, bond cannot be accepted & retrospective LUT cannot be raised for the sez sales. We will have to pay 17 lakhs with interest.

Is there any solution, we can get exemption of retrospective (july , sep & nov)  exemption of IGST for sez sales.