[Edited 03/28/2016, 04:17pm PDT.]
The IRS usually withdraws your payment on the date you specify, but
if there is a high volume of e-filing it may take a bit longer. If it
has been more than 7-10 days since your return was e-filed and accepted and the money still hasn't been withdrawn from your bank account, you can call the IRS e-file Payment Services at 1-888-353-4537.
How Direct Debit works https://ttlc.intuit.com/replies/3300043