That is mysterious. I have seen this happen once to only one of my apps on JellyBean with my old RAZR Maxx. Although that time I saw the date, was puzzled, and when I went back to look at it again 10 minutes later it was back to normal.
You might try and reboot phone into recovery and clear cache. See if that helps.
Clearing the Phone's Cache Partition:
-Turn off the smartphone
-With the device shut down, press and hold the "Volume Up", "Home" and "Power" keys
-After the smartphone vibrates once, release the "Power" key but keep pressing "Volume Up" and "Home"
-At the "Android System Recovery" screen, release all hardware buttons
-From the recovery menu, press "Volume down" to navigate to and highlight "wipe cache partition"
-Press "Power" to select the option
-After the cache partition has been wiped, a "Reboot system now" message / option will be highlighted
-Press "Power" to reboot your smartphone
