Commercial Invoice on LC submit to Bank

Our Customer sometimes will apply LC from Bank to repay the payment to us according the invoice we issue or charge them. Bank sites will request us to submit Commercial Invoice & Delivery order we bill to our customer to them, so, after 1st April 2015, is it we need to include 6% in the commercial invoice ??

We still use commercial invoice to submit to bank or we need to use Tax Invoice to submit to Bank for LC payment??

Are you referring to export sales? Generally, all exports are zero-rated, so no tax invoice required to be issued.