2005 XC90 V8 Check Engine Code Question

[ElVee]

Are the check engine codes timestamped? Can Volvo tell when a problem first occurred (if a problem came up before a warranty expired yet the car wasn't brought in until after the expiration)? My wife has a habit of not telling me when the CEL comes on. Just discovered we are getting P0134 and P0140 and am curious how longs it's been happening.