My second mortgage applies it right away, but my first mortgage does not. Because the second one has a balloon payment in 2020, I have been sending in an extra 25 to 50 dollars every week. I have an easier time budgeting it that way.
Thanks for posting this and good luck! I am about to buy a house and am going to get a 15 year mortgage. I also found out that if you pay biweekly instead of monthly, you can actually pay off a 15 year mortgage in 13 years. Maybe I will also pay extra like you so I can pay it off even sooner.
Your siggie line is an encouragement all by itself, much less all the rest of the story above it! You have some great things going on and some neat plans to tackle.