Will RGESS save tax for me?

I opened two demat accounts this financial year and have already done a few trades using one of them. Will this be an issue since the page at http://rgess.com/demat-account says “Please note you can have only one DEMAT account for the purpose of availing RGESS benefits”.

Am I eligible for RGESS tax exemption if I invest in one of the ETFs now? My annual income for this FY is less than 12 lakhs.

Thanks!