When they get around to processing all of them.  It doesn't happen a split second after the return is accepted.

It’s been days. I hope they aren’t going to charge penalties and interest. 

As long as the return was timely transmitted there won't be any penalties or interest.

Tell them to just keep treating it like an outstanding check.

Don't worry. The IRS will not forget to take it out.

On the other side of the coin double check the routing and account number of the account that was listed on the form. One little boo boo listing those numbers could lead to not having it withdrawn and the taxpayer will get a bill for the tax owed plus late payment penalty.

No but it will happen on the date that the preparer posted that the funds will be available.

Please see my reply to the one asking the question..