All Equity Investment held for more than 365 days are treated as long term when sold on the recognized stock exchanges, such long term capital gains are exempt; hence there will no withholding tax.
Long term Investment in India by NRIs without repatriation benefit does not require help of PIS Banker as there is no tax liability in that case. You only need a NRO Saving Bank Account with your bank. All your investment out of fresh purchases should have to be long term and you can transfer funds to your broker (ProStocks) before placing buy order and we will disable your account for selling investment before they become long term ( refer investment which are long term and tax free ). You can only sell securities after one year that way you will have no withholding tax and thus you don’t have to take PIS Banker services. You will not be able to repatriate funds from your NRO Saving Bank Account.