I agree you'd think disconnect could be a USB event to them so that's why I suspect DRM conversation perhaps?
Anyway, this is a change in the new firmware I think, this is the unlock device packet being sent by the new CONNECT software:
Code:
06 01 00 00 01 00 00 00 00 00 00 00 08 00 00 00 ................
2D 31 00 00 00 00 00 00 -1.....
You will note it is now 8 bytes of payload. Apparently the Reader still supports the older 4 byte model.