Screen lights up, then long delay before message notification?

This has been an issue I noticed on my iPhone 4S since updating to iOS 6, which has now worsened with the update to iOS 6.0.1. Normal operation is for the phone screen to light up and show you a message notification when you receive an iMessage or SMS. But ever since 6.0 was released I have noticed that the phone will light up for as much as a full second before any notification is displayed or sound is played by the phone indicated a message was received. Now that 6.0.1 is installed, the delay can take as much as 2 seconds or longer between the screen lighting up and any sort of notification being delivered. This is a major annoyance at night in the car, in a movie or at home in any sort of dark area because the phone will prematurely light up, and in the time it takes me to grab it and have a look there's still nothing there. I've noticed that the little red bubble that tallies how many waiting messages you have is updated when the light comes on, but the actual notification and sound are severely delayed. This was not the case before iOS 6. Anyone else noticed this or know of a way to fix it? For what it's worth, it doesn't seem to make a difference whether it's a standard SMS or an iMessage, on wifi or cellular.