it happened to me too. it's not an error. i think when cic received the medical report they changed to medical passed. my MR May 9 too and Medical passed in early june and got prearrival letter at end of june, now waitng for PPR. I don't how long it will take.Im AR early August and AOR early September.
Got MR May 9. MP early June. Had a ghost update on the same day I saw medical passed in the account. I don't know if they are related.
Also my medical says it was passed last year in October... is this a common system error?