Im sure a lot depends on where you are located but to give you an idea of when you might get a receipt notice we sent the I-751 petition on 5/25/23 to the Phoenix lockbox. We received an I-797 notice of action from the Nebraska Service Center that the validity of the permanent resident card was extended for 48 months on 6/8/23. Our case status has also changed to "Case Is Being Actively Reviewed By USCIS" after sending the receipt notice. This just means the application is being processed.