When you purchase a home with Landed down payment support, you do not make any monthly payments. In fact, you do not pay anything until you exit the agreement.
Instead, you enter into a partnership that lasts 10 or 30 years, depending on the program. You pay Landed back when you exit the partnership -- you can do this at any point during the term of your partnership, or at the end. The choice is 100% yours.
You can end your partnership in two ways: (1) by selling your home, or (2) buying out Landed (this can involve refinancing, or paying Landed back directly with funds from savings, investments, gifts, etc.)