The answer to your question is that Oregon automatically gives you a 6-month extension to October 16, 2017 if you filed an approved federal extension.
If you filed a federal extension, you do not need to fill out a separate Oregon extension form. Otherwise, print and mail Form 40-EXT by April 18, 2017.
Also, if you owe additional Oregon taxes, you'll need to submit payment by April 18, 2017 to avoid penalties. Submit your check payment with Form 40-EXT.
Thank you for asking about this.