My bankruptcy trustee directed that I file my taxes by April 15th, but I just filed for an extension. What is going to happen?

He is going to be angry.

In a chapter 13, the bk trustee will move to dismiss your case and/or object to the confirmation of your chapter 13 plan until those taxes are filed.  You need to get them done quickly or face dismissal.  Your extension does not protect you from the trustee’s requirement that you file and provide a copy of your taxes.  extension

In a chapter 7, the bk trustee may also move to dismiss your case, or, in an extreme case, even move to deny you a bankruptcy discharge (meaning that you still owe all of the debts that you thought were covered in the bankruptcy).

Get those taxes done quickly.