Don't wait.
EC 261/2004 requires that the refund be initiated within 7 days.
Presuming a cash ticket paid for with a credit card, just file a chargeback if the refund has not been initiated within 7 days of your request. Make certain that you provide copies of the e-ticket receipt, notice of cancellation, your request for a refund and any acknowledgement that a refund is due.
You gain nothing by waiting.