I found your answer today as I needed the same one. Turbotax advertising is misleading. According to First Century Bank, who administers the refund advance loan to Credit Karma, they wait until the IRS APPROVES your return, not when they ACCEPT it.
"When will I get my Refund Advance?
You'll get your Refund Advance funds typically within one hour of the IRS accepting your e-filed federal tax return (estimated late-January)."
