GST Audit under ADT -1 and matters thereof

Gst   Audit  under section 65 – we were issued a memo  ADT-01 for the Audit for the year 2018-19. We appeared before  the ACCT (Audit), put our cae in writing.      - we transferred fixed assets to a firm under an agreement for transfer of business  as on    concern. The Audit authority is taking view that for transferring fixed  assets to transfree concern a tax invoice should have been raised as this is supply.  Taking this technicality the deptt. Issued ADT – 02 and assessed CGST and SGST on entire block of fixed assets and demanded  we defray liability. We can deposit 10% of  demand and admitted tax and go for appeal. But we have decided 1) wait for the deptt to issue SCN under section 73  2) then  we shall go for installments and conclude the matter for good.  Is our plan Ok ? .  we would be obliged to get your help on  No.01  How long the deptt will take recourse to issue SCN under section 73 No.02 will this attract any penalty ? and No.3 is this kind of dues are eligible for payment under  installment  Your help will be appreciated