From a technical IT POV yes this is a likely possibility, but what I'm suggesting is in the hospitality industry, the more prevalent reason such a thing happens normally has nothing to do with ticketing system.In a controlled ticketing systems (based on room configuration), this is the only possibility.
I guess it should be some higher mgt staff kay Kiang do the bulk cancellation and forgotten to update the lower ranking staffs.
The problem usually arises due to the cruise operator's overbooking policy and/or the processes governing the quota allocation between various agencies. In heavily discounted deals, operators are more likely to take the risk of expanding the upper limits with aggressive forecasting. In the worse case scenario, bookings through agencies are usually ranked lower than those from direct booking and are the first to get cancelled.
Even amongst agencies, it is not equal. Usually there is a ranking order depending on the agency's size, commercial and personal relationship.