One of my brokers gave me this piece. I thought it was worth sharing.
Non-accelerated payments are calculated using 12 months worth of payments in a 12 month period.
Accelerated payments are calculated by incorporating 13 months worth of payments in a 12 month period. The additional month is divided equally among your payment to increase them.
Impact of Accelerated Payments
Contractual Amortization Impact on Amortization
40 years 8 years, 1 month
35 years 6 years, 3 months
30 years 4 years, 10 months
25 years 3 years, 7 months
20 years 2 years, 6 months
15 years 1 year, 8 months
10 years 1 year
5 years 5 months