Ofcourse they mean something. Confirmed by ircc agents. It mean the officer working on it made some updates at back end.I think every ghost updates means something bcoz, I received ghost updates whole week everyday and then got medical yesterday and sposnor eligibility completed. On tracker it shows sponsor eligibility completed on oct07 but I got to know on oct 6 so that means these ghost updates really means something. Same on oct 13, tracker updated but no real update and then later I checked that on that day I got my biometrics refund.