I have a question about exercise 7 in this document .

I understand that in a CMO sequential structure, payments to a tranche continue until the balance of the principal reaches zero.

In the exercise, it says that payments ought to be continued until the principal balances thereof are reduced to their respective

Planned Balances for such Distribution Date.

What are the planned balances? it doesn't seem like this info is provided.

How to calculate them, if needs be?

How do I factor them into my calculations?