QED Time travel

This night after a reboot of a VM, it was back to 8 Oct. 2012, i've lost all data between 8 Oct 2012 and now. I've check the QED file and mount on another VM, all seems OK.

This QED has a raw backfile with the base OS (debian) shared with many others QED. It has NO snapshot.

QEMU emulator version 1.1.2

Does anyone have a hint ?