Tough to answer. Often there are candidates who have passed the previous interview but did not move forward. Or candidates that were held back due to medical reasons but since cleared.
Those I described may be included in the next hire however information as to whether that would happen or who those people are is not readily available, so I would say "the rumour" as you aptly named it is accurate. It's a rumour.
I would be shocked if there was no new recruitment for the next class to get the numbers required for a class.
Time will tell but I'm betting on another recruitment still to come this fall.