The IRS always says it sent it to a "bank" because all it sees is the routing number and account number, so it doesn't know the difference. A prepaid debit card uses an underlying bank account and routing number just like a bank.
The IRS FAQ page says to allow up to 5 days due to variations in bank processing times and procedures. But it normally doesn't take that long.
There could be another link in the chain. Did you have any TurboTax fees that you chose to pay out of the Federal refund? If so, the funds will go first from the IRS to an intermediary bank where the fees are subtracted. Then that bank sends it on to your card. If you chose that method to pay the fees, we can tell you how to log in and check on your funds at the level of the intermediary company.
