I need to verify if in fact my deceased father's CPA actually filed an extension with the IRS as she said she would. I have reason to believe she may have a personal grudge against myself, the successor trustee. If I call the IRS with the EIN number, can they look up in their system if the extension was in fact filed. This would have been nearly 3 weeks ago. Would the extension already be in the IRS system? It would likely have been an electronic filing.