It may be that a monk has committed two offenses entailing suspension, both concealed for two months. He’s aware of one month, but not the other. He asks the Sangha for one month probation for the month he’s aware of, which he gets. While on probation, he finds out about the other month. He considers all this and thinks, ‘Let me ask the Sangha for probation for an additional month for those two offenses.’ He asks and gets it. Counting the previous month, that monk must stay on probation for two months.