26 November 2016
If migration is not done within allowed time then you have to take new registration under GST and if you have any carried forward input credit you will not be able to claim.
VK
06 December 2016
If you are required to get registered under GST after GST is applicable, you have to apply and get yourself registered. In case of non-registration penalty is Rs. 10k or amount of tax whichever is higher.