I know many such parents, and they never end a school year with an outstanding balance. But their tuition payments cannot follow a schedule to accommodate weekly or biweekly payroll.
I would expect that there is administration that understands this.
It’s not only a matter of the administration understanding, it’s also a matter of being able to make payroll, which is what this thread is discussing.
Although, if they know a certain percentage of the parents have seasonal income, it might be possible to obtain short term loans from some understanding wealthy supporters.