https://www.chase.com/index.jsp?pg_name=ccpmapp/shared/assets/page/Online_Rewards_FAQ
It's incredibly difficult to not use up the credit if you're traveling even once per year. @Jose even loading up a Metrocard counts.
That leaves you with $150 to make up. There's various ways to use the points but the most straightforward one is using them at 1.5 cents per point through the Chase travel portal, meaning you need 10,000 points. If you spend on nothing but travel and dining using the card (those get 3x) that leaves you to spend $3,333. What Jose is describing with the Freedom Unlimited is to stick non-travel non-dining purchases onto the card so that the 1.5% back on that turns into an effective 2.25% back after you transfer the points to the Reserve.