For those dates and those cities, "bet the ranch on it." Just my opinion. Whether that means you should convert to Freedom Award depends on how you value awards versus dollars and flight date/time/length flexibility.

How many travelers? The 6:50 AM nonstop from TPA-BWI is still available @ $148, so if there are two in your party you could try using one freedom Award for two people on the outbound and pay for the return, if that seems like a better value proposition for you.

If your dates are a little bit flexible you could use a web site with reasonably modern search capabilities and find that you could fly that route round-trip (different airline, connection involved) in that time frame for $280. Is that a tradeoff worth a Freedom Award? Only you can say.