Tnvat - generation of c form

Yes you can generate C form immtly

Sir,  Your Purchase Interstate purchase against form c , Sales Local Sales or Interstate sales. Please verify both side vat commodity and cst commodity is same. for eg. your interstate purchase 2130 your vat commodity is also 2130. If any one side is not available form c not generated. Please check previous software www.tnvat.gov.in , Know Your eligible commodities and cst registration certficate available for specific commodity go to circle update your commodities 

yes your can generate c form for april to june quarter now. In case you already generated before filing revised return, in that case also you can cancell c form and can generate fresh c forms as per revised returns.