Underpayment and payment holidays
It is a period when you could reduce your monthly payments by paying interest only, or even discontinue them by deferring the full amount of the payments.
If you struggle to meet payments throughout the early years of the mortgage, underpaying or arranging a payment holiday for months and even years might ease the burden. However, you must bear in mind that:
If you only pay interest, monthly payments are smaller, but the amount of capital borrowed will remain unchanged.
If you do not pay interest or capital, interest will accrue and the capital will also increase.