Absolutely. I have had this problem many times with carriers like Virgin Mobile, the prepaid stuff. I also had this problem with the old ATT company Cell One, and got into lots of trouble with the ex. Just cuz it was sent at a certain time does not mean it didn’t get lost in the stratosphere somewhere and arrive hours later. Plus you send, out of coverage, and later it resends. Don’t rely on the bill. Why do you ask?