Most replacement cost policies pay ACV after the 5th year, BUT, after you purchase an equal or better repalcement coach, they will then (additonally) pay the difference between ACV and your original invoice price. So you do still have replacement coverage, through however many years they promised. Give National General a call and have them explain their policy to you.
This procedure is pretty standard in the vehicle insurance industry. After the 5th year, they only pay replacement if you actually replace it. This can be a problem if you still have a big loan outstanding. ACV might not be enough to pay off the loan and you probably can't buy a new one until the old loan is satisfied.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL